Potato Riffs Retrospective

Background

Just over a year ago we launched the Potato Diet Riff Trial, the first of its kind.

The riff trial is a new type of study design. In most studies, all participants sign up for the same protocol, or for a small number of similar conditions. But in a riff trial, you start with a base protocol, and every participant follows their own variation. Everyone tests a different version of the original protocol, and you see what happens.

As the first test of this new design, we decided to riff on one of our previous studies: the potato diet. For many people, eating a diet of nothing but potatoes (or almost nothing but potatoes) causes quick, effortless weight loss, 10.6 lbs on average. It’s not a matter of white-knuckling through a boring diet — people eat as much (potato) as they want, and at the end of a month of spuds, they say things like, “I was quite surprised that I didn’t get tired of potatoes. I still love them, maybe even more so than usual?!”

Why the hell does this happen? Well, there are many theories. The hope was that running a riff trial would help get a sense of which theories are plausible, try to find some boundary conditions, or just more randomly explore the diet-space. We thought it might also help us figure out if there are factors that slow, stop, or perhaps even accelerate the rate of weight loss we saw on the full potato diet.

In the first two months after launching the riff trial, we heard back from ten riffs. Those results are described in the First Potato Riffs Report. Generally speaking, we learned that Potatoes + Dairy seems to work just fine, at least for some people, and we saw more evidence against the idea that the potato diet works because you are eating only one thing (people still lost weight eating more than one thing), or because the diet is very bland (it isn’t).

Between January 5th and March 18th, 2024, we heard back from an additional seventeen riffs. Those results are described in the Second Potato Riffs Report. Generally speaking, we learned that Potatoes + Dairy still seems to work just fine. Adding other vegetables may have slowed progress, and the protein results were mixed. However, the Potatoes + Skittles riff was an enormous success. 

Between March 18th and October 9th, 2024, we heard back from an additional eleven riffs. Those results are described in the Third Potato Riffs Report. Generally speaking, we saw continued support for Potatoes + Dairy.

The trial is closed, but since the last report, we’ve heard back from an additional two riffs, which we will report in a moment. This gives us a total of 40 riffs in this riff trial. Note that this is not the same as 40 participants, since some people reported multiple riffs, and a few riffs were pairs of participants.

Raw data are available on the OSF.

Last-Minute Entrants

Participant 87259648 did a Fried Potatoes riff, specifically, “mostly fried in a mix of coconut oil and tallow or lard” and continuing her “normal daily coffees with raw whole milk, heavy cream, honey and white sugar.”

Despite consuming only “around 30 percent potato on average”, she lost a small amount of weight and “found [the] diet to be easy and enjoyable, I never felt sick of potato although I did have a hard time getting myself to eat MORE potato each day.”

Participant 80826704 was formerly participant 41470698, but asked for a new number to do a new kind of riff. In Riff Trial Report Two, he had done Potatoes + Eggs as participant 41470698 and lost almost no weight. This time, he did a full potato diet and lost a lot of weight, more than 13 lbs: 

This definitely fits with our suspicion that eggs may be related to weight gain, and the observation that eggs often contain high concentrations of lithium.

Summary

Let’s recap all the riffs. Here’s a handy table:  

Mean weight change was 6.4 lbs lost, with the most gained being 5.2 lbs and the most lost being two people who both lost 19.8 lbs. One person gained weight, one person saw no change, one person reported no data, and the rest lost weight. One person also gained 6.3 lbs on “Whole Foods” + Chocolate, but this was not a potato diet (only about 10% of her diet was potatoes). 

Here are all the completed riffs, plotted by the amount of weight change and sorted into very rough riff categories: 

There are also a large number of people who signed up, but never reported closing their riff. We’re not going to analyze them at this point, but all signup data is available on the OSF if you want to take a look at the demographics. 

Things we Learned about the Potato Diet

The potato diet continues to be really robust. You can eat potatoes and ketchup, protein powder, or even skittles, and still lose more than 10 lbs in four weeks. 

The main thing we learned is that Potatoes + Dairy works almost as well as the normal potato diet. There were many variations, but looking at the 10 cases that did exclusively potatoes and dairy, the average weight lost on these riffs was 9.2 lbs. This is pretty comparable to the 10.6 lbs lost on the standard potato diet, suggesting that Potatoes + Dairy is almost as good as potatoes by themselves (though probably not better). 

We didn’t see much evidence that there might be a protocol more effective than the potato diet. This is sad, because it would have been really funny if Potatoes + Skittles turned out to be super effective. 

That said, three riffs did do unusually well, and it’s still possible that there is some super-potato-diet that causes more weight loss than potatoes on their own, or that’s better in some other way. 

There’s some evidence that meat, oil, vegetables, and especially eggs make the potato diet less effective. But with such a small sample, it’s hard to know for sure. This could be a productive direction for future research. You could organize it as an RCT, and compare a Just-Potato condition to a Potato + Other Thing condition. Or an individual could test this by first doing a potato diet with one of these extra ingredients for a few weeks, then removing the extra ingredient and doing a standard potato diet for a few weeks as comparison.

The strongest evidence is against eggs, because participant 41470698 / 80826704 did exactly that. First he did a Potatoes + Eggs riff and lost only 1.8 lbs. Then he did a standard potato diet and lost 13.2 lbs. That’s not proof positive, but it’s a pretty stark comparison. If that happens in general, it would be hard not to conclude that eggs stop potatoes from working their weight-loss wonders.  

Current Potato Recommendation

If you want to try the potato diet for weight loss, our current recommendation is this funnel:

  1. Start by getting about 50% of your diet from potatoes and see how well that works.
  2. If you want to be more aggressive, switch to Potatoes + Dairy. Try to get at least 95% of your diet each day from potatoes and dairy products, but don’t worry about small amounts of cheating.
  3. If you want to be more aggressive, switch to the original potato diet. Try to get at least 95% of your diet each day from potatoes, but don’t worry about small amounts of cheating.
  4. If you want to be more aggressive, switch to a strict potato diet. Try to get almost 100% of your calories each day from potatoes, allowing for a small amount of cooking oil or butter, salt, hot sauce, spices, and no-calorie foods like coffee.

If dairy doesn’t work for you for some reason (like you’re a vegan, or you just hate milk), consider replacing Step 2 with a different riff that showed good results, like Potatoes + Lentils or Potatoes + Skittles.

Remember to get vitamin A. Mixing in some sweet potatoes is a good idea for this reason.

Remember to get plenty of water. Thirst can feel different on the potato diet, you will need to drink more water than you expect.

Remember to eat! In potato mode, hunger signals often feel different. But if you don’t eat you will start to feel terrible, even if you don’t feel hungry. If anything, eating a good amount of potatoes each day may make you lose weight faster than you would skipping meals. 

If the potato diet makes you miserable, try the three steps above. If you try those three steps and you’re still miserable, stop the diet. 

Things we Learned about Doing Riff Trials

This is the first-ever riff trial. But it won’t be the last. So for the next time someone does one of these, here’s what we’ve learned about how to do them right.

#1: It Works

We hoped that riff trials would use the power of parallel search to quickly explore the boundary conditions of the base protocol, and discover what might make it work better or worse. 

This works. We had suspected that dairy might stop the potato effect, but we quickly learned that we were wrong. We saw that the potato effect is also sometimes robust to lots of other foods, like skittles. And we saw that other foods, like eggs and meat, seem like they might interfere with the weight-loss effect.

#2: You May Have to Encourage Diversity

That said, there was not as much diversity in the riffs as we might have hoped. 

Most people signed up for some version of Potatoes + Dairy. This was great because it provided a lot of evidence that Potatoes + Dairy works, and works pretty damn well. But it was not great for the riff trial’s ability to explore the greater space of possible riffs. 

In future riff trials, the organizers should think about what they can do to encourage people to sign up for different kinds of riffs. If you don’t, there’s a good chance you’ll find that most of your scouting parties went off in the same direction, and that’s not ideal if you want to really explore the landscape.

One way to do this would be to run a riff trial with multiple rounds. First, you have a small number of people sign up and complete their riffs. Then, you take some of the most interesting riffs from the first round and encourage people to sign up to riff off of those. You could even do three or four rounds. 

In fact, this is kind of what we did. Since we reported the results in waves, and had rolling signups, some people were definitely inspired to try things like Potatoes + Dairy or Potatoes + Lentils because of what they saw from completed riffs. But we could have done this even more explicitly, and that might be a good idea in the future.

#3: Riff Trials Harness Cultural Evolution

There’s no formal skincare riff trial. But it does kind of exist anyway. People get interested in skincare, and go look at other people’s routines. They copy the routines they like, but usually with some modifications. This is all it takes for skincare protocols to mutate, combine, and spread through the population, getting better and better over time.

The same is true of any protocol floating out there in the culture, including the potato diet itself. Even if we hadn’t run the riff trial, people would have experimented with potato diets for the next 10 or 20 years, trying new variations and learning new things about the diet-space. But this process would have been slow, and it would have been hard to tell what we were learning, because the results would have been spread out over time and space.

The fact that we planted our flag and ran this as a riff trial didn’t change the nature of this exploration. But making it one study, clearly marking out its existence, definitely sped things up, and helps make all the riffs easier to compare and interpret. 


87259648 – Fried Potatoes

Riff 

Potatoes, mostly fried in a mix of coconut oil and tallow or lard. I will continue with my normal daily coffees with raw whole milk, heavy cream, honey and white sugar. Maybe occasional fruit on cheat days but mostly just potatoes, dairy, coconut oil, tallow, coffee and honey/sugar. 28 days. My reasoning for choosing this is that fried potatoes are delicious, i really don’t want to give up my coffee routine, or waste the raw milk that i get through a cow share, and anecdotally, coconut oil and stearic acid have both been reported to help with weight loss.

Report

So I didn’t lose a lot of weight, but I definitely lost somewhere between 3 – 6.5 lbs (hard to tell due to fluctuations in water weight) and an inch off my waist despite doing a pretty relaxed version of the diet. 

What I ended up doing was a diet of around 30 percent potato on average (even though I only ate potatoes for dinner and “grazed” on smallish things throughout the rest of the day, it was hard for me to get past around 30 percent potato calorie-wise). The rest of my diet was mostly dairy (raw milk, heavy cream, sour cream, butter, cheese and occasional ice cream), fruit, sugar (and sugary drinks), honey, chocolate and saturated fats (coconut oil and beef tallow).

I rarely boiled the potatoes so the potato portion of the diet was mainly peeled yellow or red potatoes pan-fried in a mixture of tallow and coconut oil, baked russet potatoes with the skins, or roasted red and yellow baby potatoes with the skins.

I occasionally supplemented extra potassium, as well as other supplements. Around day 5 I started drinking coconut water in order to get extra potassium.

I found this diet to be easy and enjoyable, I never felt sick of potato although I did have a hard time getting myself to eat MORE potato each day. The skins didn’t seem to bother me. Something about the diet definitely seemed to have an appetite lowering effect, although my appetite did fluctuate from day to day. I never intentionally cut calories or deprived myself of anything I really wanted. So even on the very low calorie days I ate as much as I felt like eating that day. (i am used to doing extended fasts so this is not super unusual for me, but I DO think that the extra potassium or something DID result in more days than usual where I didn’t feel like eating as much).

I didn’t exercise any more or less than I usually do.

My husband and another male family member did even less strict versions of the diet along with me (potatoes for dinner, whatever else they wanted the rest of the day) and they both seemed to lose more weight than I did, but they didn’t keep track of any data. I’m a 49 year old female, the other two men are 49 and 66. In the last couple years it has gotten much harder for me to lose weight, and I have been pretty fatigued in general. I didn’t notice any extra energy on this diet, but appetite did often seem suppressed.

I didn’t observe any noteworthy reduction in pulse or body temperature over the course of the diet. Three weeks after finishing the diet I have not been able to keep the weight off and am back up to 190.

I kept track of everything in the Cronometer app, so if you have any questions I can access some data that’s even more specific from there, let me know!

80826704 – Only Potatoes

Riff 

Formerly participant 41470698, who asked for a new number: “I would like to try the full potato diet at some point during 2024. Could you prepare a new Google Sheet for me for this purpose?”

Report

I completed the potato only version in August, but neglected to send you a report. Happy to report that I’ve completed it and filled the 4 week sheet.

In terms of feeling it was very similar to my riff experiment. In terms of results this has been completely different. One thing I am now throughly convinced about is the “ad libitum” part. I am hungry, I eat. It’s so simple it’s scandalous, but it’s been buried under years of well meant status quo advice.

From that point it simply matters which food types I eat. Even if the lithium hypothesis turns out wrong, this part I am thoroughly convinced about now.

Difficulty

In a way this was easier than potatoes + eggs. One reason I remember for this was the forced pre-planning. Because I knew I was going to eat only potatoes I generally tried to peel way more potatoes than I was hungry for. Because of this, for the next meal I would have potatoes already lying around. I could then eat those as-is, or more tasty, (re-)baking them in a frying pan.

Somehow I had less inclination to cheat.

I’ve also gone to McDonalds like 6 times, ordering only fries without sauce. And a lot of fries from a Snackbar (https://nl.wikipedia.org/wiki/Snackbar). It’s super convenient when going by train to just order a big portion of fries without sauce.

Fun stuff

Potatoes are fucking delicious by the way. I’ve taken to eating them without sauce, because now it just feels like potatoes with sauce taste like sauce. And then I’m missing the potato flavor. Maillard reaction for the win.

With a group of friends I did a “potato tasting”. I bought 8 breeds of potatoes and cooked them with the oven or boiled. So we tasted 16 different kinds. People were truly surprised by the amount of variation.

My surprise was mostly about how difficult the different breeds were to peel. Some potatoes are truly monsters.

Krinn Post 2: A Year and Change

Last time you heard from her, Krinn had just put out a tumblr post titled An Ad-Hoc, Informally-Specified, Bug-Ridden, Single-Subject Study Of Weight Loss Via Potassium Supplementation And Exercise Without Dieting. After losing 6 lbs in our Low-Dose Potassium Community Trial, she decided not to stop as planned but instead to keep going, and in fact go even harder. Eventually she ramped up to around 10,000 mg potassium a day, and lost even more weight. 

Krinn also added an exercise habit that she described as a “naïve just-hit-the-treadmill exercise regimen”. Even with this in mind, her results still seem remarkable, because most people do not lose 50 lbs from starting a moderate treadmill habit: 

We published a short review of that original post on this here blog of ours. That was in July 2023. Now, Krinn is back, and more powerful than ever, with an untitled post we’ll call A Year And Change After The Long Post About The Potassium Experiment (AYACATLPATPE). 

The long and short of it is that Krinn kept taking high doses of potassium and kept losing weight, eventually reaching her goal of 200 lbs. There was a long plateau in the middle after she first brushed up against her goal, but she maintained the original weight loss and eventually lost the remaining weight:

In personal communication (see very bottom of this post), Krinn noted that:

One of the few things the graphs say really, really, really loudly is “Krinn lost 30+ pounds _and stayed that way for at least a year._” … one of the overwhelmingly common failure modes of existing interventions: people lose some weight and then gain some weight and end up fairly close to where they started. Whatever else happened in my experiment, it sure wasn’t that: I lost a significant amount of weight and then _stabilized._ That seems important.

This time we don’t have much to add, but as before we wanted to reproduce her post for posterity. And we do have a few thoughts, mainly: 

This seems like more evidence that high doses of potassium cause weight loss. It suggests that potassium is probably one of the active ingredients, maybe the only active ingredient, in the weight loss caused by the potato diet. Krinn was taking about as much potassium as you would get if you were eating 2000 calories of potatoes per day, and experienced similar weight loss. 

It’s good to be skeptical of single case studies, however rigorous and careful they may be, but here are a few things to keep in mind: 

Remember that participants in the Low-Dose Potassium Community Trial lost a small but statistically significant amount of weight (p = .014) on a dose much lower than what Krinn was taking — only about 2,000 mg of potassium a day on average, compared to Krinn’s ~10,000 mg per day. This can’t confirm the effects of the higher dose, but it is consistent with Krinn’s results, and the final sample size was 104 people.

There’s also at least one successful replication. Inspired by Krinn’s first report, Alex Chernavsky did a shorter potassium self-experiment and lost about 4 pounds over a two-month period, otherwise keeping his diet and exercise constant. He also provided this handy table: 

Finally, we know of two other people who are losing weight on high-potassium brines, at least one of them without any additional exercise. They’re both interested in publishing their results, probably in early 2025. So watch this space. :​) 

As before, we want to conclude by saying that Krinn is a hero and a pioneer. She is worth a hundred of the book-swallowers who can only comment and couldn’t collect a data point to save their life. If you want to do anything remotely like what Krinn did, please feel free to reach out, we’d be happy to help.


Here’s a reproduction of Krinn’s full report as it appears in her tumblr post:

A Year And Change After The Long Post About The Potassium Experiment 

A year and change after the long post about the potassium experiment, I reached my weight-loss goal. This is a quick, minimally-structured thought-dump about it. As before, this is part of a wider conversation that starts with A Chemical Hunger.

Methodology: I mostly kept doing what I’d been doing. Turned up the exercise dial a bit, turned down the potassium dial a bit. Both still, AIUI, quite high compared to American baseline. Some bad news — in addition to whatever confounding factors were present last time, there’s a few extra ones now from my life in general going very poorly. As before, here’s the data, Creative Commons Zero, good luck with whatever you try on it. After making it to one year of being fairly diligent, I decided to let things vary and see what happened — on the one hand, I’d gotten far enough towards my personal goal that I wasn’t too fussed about the last 10%, and on the other hand, if this works in general and even work when you’re kinda half-assing it, that too is great news.

Interpretations: There’s multiple ways this could go. Here are a few that were easy to think of.

  1. Potassium or potassium-plus-exercise caused me to lose weight
  2. Exercise caused me to lose weight and potassium was irrelevant
  3. Something else caused me to lose weight

I would prefer to believe that potassium-plus-exercise caused me to lose weight. The data I have and my experience of gathering/being that data, to some extent support that conclusion. Flipping that around, if I ask “does that data rule out this conclusion?” no it absolutely does not. But it’s important to note that the exercise-only conclusion is only slightly less-well-supported and the none-of-the-above explanation is much-less-well-supported but certainly not ruled out. I have a preferred explanation, but all three of these explanations are live.

My subjective experience of the thing was that there was an easy part and a hard part. In the easy part I lost weight at a pretty rapid and consistent pace. In the hard part, my weight changed less and went back and forth more than it went down. If you buy into SMTM’s “something is screwing up people’s lipostats” theory, this is very consistent with that theory: potassium reduced or removed the something, my weight briskly dropped back to a healthy range (the first 9 months of the graphs) and then stabilized. However, the competing theory of “Krinn was super out of shape and then she started exercising” is also supported by the graphs (not shown on the graphs: my fairly poor 2022 exercise habits — my long-term exercise habits have had some good stretches, but the plague years did not do good things for me there!). I’m not sure whether it matters that I shifted from mostly treadmill time to having a couple of walks around the neighborhood that I can do pretty much on autopilot (shout-out to Mike Duncan’s Revolutions, this show is the first time podcast as a medium has clicked for me and it’s a great show). I do think, though, that exercise is a bit more complicated than I was really grasping. That, in turn, makes me glad that I’m tracking three exercise metrics rather than just one — if I was going to track only one, it’d be exertion, but exertion, exercise minutes, and step count, together make it possible to at least take a guess at what qualities a day’s exercise had.

Regarding my own questions from the first post: 

How safe is this? When I made the first post I was antsy about “adding this much potassium to your diet is probably safe for people in generally good health” but now I’m pretty sure it’s true. Some health problems can take a long time to present themselves, but adding this much of something to your diet for two years and having it be fine, is pretty persuasive evidence that the thing is probably fine. It could still easily turn out to have negative health impacts that are important, but a huge swath of the things you’d be worried about, are vanishingly unlikely once you’ve hit the point of “I’ve been taking this for two years and I’m fine.”

Does this replicate? Well, it’s self-consistent for me, and I don’t want to gain 50 pounds and try again. I did not like the shape of my body at +50 pounds from where I am now! So this is a question for others.

How much do other nutrients matter? I don’t know. Mostly not equipped to rigorously check.

Does HRT matter? I’ll let you know if I can get back on HRT. I would definitely like to investigate this.

Does dieting matter? Probably: my diet changed involuntarily over the course of two years and that certainly matters to some extent, but one of my ground rules is that I’m focusing on controlling exercise and potassium, the things I can control. Diet is far more complex and also in my life particularly, more susceptible to unplanned, involuntary change, so I’m writing it off as a factor.

Does this help with cannabis-induced hunger? I think I was off-base/over-optimistic with this one and it either doesn’t matter or matters a small amount.

Is there a point where I get really hungry/tired or start accidentally starving? I did not reach such a point. I felt basically fine the whole time.

I was cooking with this though:

If you tell someone you want to lose weight and would like their advice, it is overwhelmingly likely that the advice will involve exercising more. Everyone has heard this advice. And yet, as Michael Hobbes observes  in a searing piece for Highline, “many ‘failed’ obesity interventions are successful eat-healthier-and-exercise-more interventions” that simply didn’t result in weight loss. Even if we as a society choose to believe “more exercise always leads to weight loss, most people just fuck up at it,” that immediately confronts us with the important question, why do they fuck up at it? and its equally urgent sibling, what can we learn from those who succeed at it to give a hand up to those who have not yet succeeded?

Conclusion: I’m gonna keep writing things down in my spreadsheet for the same reasons as last time. I’m not sure what exactly I’m going to do as far as twiddling the factors, because now my main goal is somewhere between “don’t gain weight again” and “see what happens,” but I do know that writing down what happens is Good Actually, so I’m going to keep doing that.


Slightly after publication, Krinn sent us these comments, which she agreed we could publish: 

Personal Communication

Dangit now I’m having the first draft effect: writing the first draft and sleeping on it tells me things I should have written. In this case, I think there’s a plausible reading that my experience supports the “potassium does something good at a high enough effect size to care about” line of argument because while the peaks of how much effort I put in were fairly high — the periods of combined high exercise and high potassium intake — the most noticeable effect was when I was ramping up on both of those in the first 9 months, and when I was in just-bumbling-through-like-an-average-human mode, the effect didn’t reverse itself. There were plateau periods and there were slow-reversion periods, but there was definitely no “you slacked off and now there’s rapid weight gain mirroring the rapid weight loss” effect. I think that’s positive? I think it’s plausible to read it as “once I got the majority of the weight loss effect, locking in that benefit was easy.”

In any case one of the questions I was interested in was “if this works, does it work well enough that an average person can successfully implement it?” and I am now convinced that that’s a clear “Yes”.

I wouldn’t say there’s any part of this experiment that I’m actively unhappy about, but I do find it a little frustrating that this is basically just another piece of evidence on the pile of “here’s something that is consistent with the lithium/potassium hypothesis, but that is also consistent with some other stuff, and my main observation is that Something Happened” — intellectually I feel sure that much solid science is built by assembling big enough piles of such evidence and then distilling it into “now we know Why Something Happened,” but putting one single bit of evidence on the pile is still something where I need to make my own satisfaction about it rather than having a well-established cultural narrative rushing to bring me “yes! you did the thing! Woohoo!”

Also thinking more about the potassium experiment I’m having one of those “hold on a minute, this should have been obvious to me” moments — one of the few things the graphs say really, really, really loudly is “Krinn lost 30+ pounds and stayed that way for at least a year.” That’s one of the crucial parts of the whole obesity thing, that second half, right? That’s one of the overwhelmingly common failure modes of existing intervention: people lose some weight and then gain some weight and end up fairly close to where they started. Whatever else happened in my experiment, it sure wasn’t that: I lost a significant amount of weight and then stabilized. That seems important.

Yessssss I get the smug clever-kitty feeling, this is exactly why I have that “ratchet” column in the spreadsheet: the last ratchet-tick day from more than a year ago (i.e. it’s locked in) was July 10th 2023, on which day my week-average weight was 212.4lbs, down 33.6lbs from the start of the year.

So that early period of dramatic weight loss is noteworthy because we can be confident that whatever the cause was — potassium, exercise, or something else — it caused durable weight loss, which is exactly the thing we are looking for.

This is a conclusion we couldn’t have reached in July 2023, with the major writeup I did, because at that point “something else happens and Krinn gains the weight back” was very possible, was one of the likely answers to “what comes next?”

Third Potato Riffs Report

For many people, eating a diet of nothing but potatoes (or almost nothing but potatoes) causes quick, effortless weight loss. It’s not a matter of white-knuckling through a boring diet — people eat as much (potato) as they want, and at the end of a month of spuds they say things like, “I was quite surprised that I didn’t get tired of potatoes. I still love them, maybe even more so than usual?!” And some people lose a similar amount even when eating only 50% potato.

Why the hell does this happen? Well, there are many theories. To help get a sense of which theories are plausible, try to find some boundary conditions, or just more randomly explore the diet-space, we decided to run a Potato Diet Riff Trial

In this study, people volunteer to try different variations on the potato diet for at least one month and let us know how it goes. For example, they might eat nothing but potatoes and always cook their potatoes in olive oil. Or they might eat nothing but potatoes and leafy greens. Or they might eat nothing but potatoes but always eat their potatoes with ketchup. 

The hope is that this will help us figure out if there are other factors that slow, stop, or perhaps even accelerate the rate of weight loss we saw on the full potato diet. This will get us closer to figuring out why potatoes cause weight loss in the first place, and might get us closer to curing obesity. We might also discover a new version of the diet that is easier to stick to, or causes more weight loss, or both. 

In the first two months after launching the riff trial, we heard back from ten riffs. Those results are described in the First Potato Riffs Report. Generally speaking, we learned that Potatoes + Dairy seems to work just fine, at least for some people, and we saw more evidence against the mono-diet and palatability hypotheses. 

Between January 5th and March 18th, 2024, we heard back from an additional seventeen riffs. Those results are described in the Second Potato Riffs Report. Generally speaking, we learned that Potatoes + Dairy still seems to work just fine. Adding other vegetables may have slowed progress, and the protein results were mixed. However, the Potatoes + Skittles riff was an enormous success. 

Since then, we’ve heard back from 11 new riffs. (Specifically, these are the riffs we heard back from between March 18th and October 9th, 2024.)

A few riffs are ongoing, but signups have slowed to a crawl. So while there may be a few more riff trial results in your future, signups are now closed. We may do more potato diet studies in the future, perhaps even another riff trial, but we are going to wrap this one up for now. Expect a final riffs retrospective around January 2025. 

But let’s see what we’ve learned so far. First we’ll review the overall results, and talk about our interpretation. Then, at the end we’ve included the actual riff proposals and reports from all 11 participants in an appendix, if you want to read about them in more detail.

Unless otherwise indicated, weight loss numbers are over a period of about 28 days, comparable to the original Potato Diet Community Trial. 

Potatoes + Dairy

Participant 07566174 ate “Potato plus a bit of dairy, ice cream for a treat”. At the end they said, “overall very successful despite rampant cheating!” and you know what, that’s entirely right: 

In this case, cheating wasn’t “take a day-long break from eating potatoes”, instead it meant more like “ate less than 100% potato”. For example, one cheat day entry said: “Had some cake, and a couple chocolates. Otherwise, potato. Plus a beer instead of ice cream.”

This participant actually gave us six weeks of data, here is the longer chart: 

Participant 28818306 took to the true spirit of the riffs trials, “trying to combine what looks like working riffs (potatoes + dairy + lentils)” along with adding “some lettuce to the mix to see if it keeps working”. 

This worked ok. “It went well in the first 2 weeks,” 28818306 reported, “the other 2 were kind of slow, and harder to follow.”

Participant 92679541 did a riff of potatoes + oil + dairy (mainly cream and butter), with a more casual protocol and cheating most days, but had to stop the diet early. Despite all this, he lost a couple of pounds:

Participant 97027526 did a riff starting with potatoes plus butter, ghee and spices, and added raclette cheese after a few days. 

Chalk another one up for the potato diet making people fall even deeper in love with potatoes: “I discovered I LOVE baked potatoes (first cooked in the microwave then finished off in the oven to crispen them up) and over 70% of my potatoes were cooked like that. … I am surprised that after four weeks I still really like potatoes! I’m going to continue with the potatoes for a while”. 

She lost exactly 10 pounds over 28 days:

We then later received an update, where she said, “I am almost at the end of 8 weeks and still going strong. … My diet now exclusively consists of baked potatoes, butter, salt (a few pinches once a day), pepper and sometimes garam masala. … I’m not nearly as hungry as I used to be.”

Between Day 1 and Day 53, she lost a total of 15.9 pounds: 

Potatoes + Meats

Several people tried riffs that aimed for the most classic meat & potatoes.

50108266 and 20953986 are a husband and wife team who started with the plain potato diet then added organ-based meat. Their full protocol was a bit complicated, see the appendix for more detail.

The results: Two weeks of just potatoes, “lost weight, but hated it”. Two weeks of potatoes + organ meat, “lost less weight, enjoyed much more. We will keep going.” It’s interesting that such a small change could so strongly affect their perceived enjoyment of the diet, especially while not strongly affecting how quickly they lost weight.

54084282 said, “I feel a diet that I could stick to for 30 days would be potato, bacon, black coffee, and Guinness. The bacon would help supplement fat and protein missing from the potatoes and reduce the need for extra seasonings. The coffee and Guinness are mostly for personal preference.”

Thirty days later, we got this update: “I have modified from my original riff! I’d characterize my current plan as fermented food/drinks + potatoes, along with a serving or two of protein daily. It is resulting in steady weight loss while alleviating the bloating and unpleasant constipation feeling that I experienced initially. I have lost about 5 pounds this month while feeling generally satisfied and still surprisingly not tired of potatoes. Only real remaining issue is eating out. I just cannot bring myself to order only French fries for a meal (especially around the kids). I just cheat in those situations but still manage to steadily drop weight, lol.”

Checking the data now, we see that 54084282 kept recording data up to day 58, and continued the trend of losing weight: 

83842317 says, “potato + meat (chicken, beef, pork, fish)”. Then after the diet, “The convenience of eating tater tots, hash browns, chips, fries, and meat has been very easy and I’ll be sticking to it”.

There was no weight entry for Day 29, so here’s 83842317’s data up to the last weight entry on Day 34:

Participant 22179922 did a riff she came to call “potatoes and cows”, starting with potatoes and ramping up to first include dairy and then include other animal products (see appendix for full details). 

Chocolate-Style Riffs

Two people did riffs that sort of involved chocolate.

59960254 did something like “Potatoes with Fire in a Bottle Characteristics”, meaning potatoes and a small amount of fat from sources like butter, tallow, coconut, cacao, etc. and also including fruit, honey, dates, and dark chocolate. This lead to a weight loss of exactly 10 lbs by Day 29:

We actually have 12 weeks of data from this participant, here is the longer version. The fluctuations in the middle are a sad story that have little to do with the diet itself; his cat got sick around the three week mark.

95078099 followed a riff of “potato + soy products + chocolate”. Note that he started off quite lean, with a BMI of around 20, but that “this is the result of a long, hard calorie restriction. My personal aim is not to lose weight, but to keep the weight down. If I stay at the same weight, and not drift up by a few pounds, I’d consider that a success!” So in this case the question is not really whether 95078099 can lose weight on the potato diet, but whether he can maintain weight on the potato diet without calorie restriction.

Ultimately, 95078099 lost 1.5 lbs between the first and the last measurement over four weeks. But based on the moving average, he concludes, “for myself, and for the purpose of keeping my weight down, I’d consider my potato riff ineffective.” See the appendix for a lot more detail, including additional charts with several years of data.

Skittles Update

Previously, participant 22293376 tried a Potatoes + Skittles riff, and was “astonished at just how well it went.” Here are those original results: 

This was in January 2024. By July, he had started gaining weight and decided to do a second run of the riff, with some minor changes. This time it was potatoes plus: butter, oil, sweet potatoes, “low-calorie vegetables (onions, peppers, broccoli, green chile, etc.)”, and “skittles (in moderation)”. And for this second round, the results look like this: 

The y-axis is fixed to match 22293376’s previous graph.

22293376 says, “I generally didn’t eat more than 20-30 skittles a day, and sometimes none. I don’t really recommend eating skittles-only meals but you do you!” Also check out the appendix for more detail on this riff. 

Interpretation

As before, Potatoes + Dairy seems to work for many people, and it seems quite resistant to cheating. Every Potatoes + Dairy riff in this roundup lost some weight, and some lost as much as 10 lbs.

People lost some weight on different versions of Potatoes + Meats, but this seems to be inconsistent. It’s possible that the kind of meat, or its origin, could make a difference. 

“Potatoes with Fire in a Bottle Characteristics” worked quite well. While the sample size is only one, it’s a nice proof of concept. These various fats and sweets don’t seem to interfere at all with the potato effect, at least not for this participant. 

It’s also wonderful to have a skittles replication. The results are still from the same person, which means we can’t be sure if it will work equally well for other people, but it’s nice to see that this can happen twice. And it’s certainly more evidence against the idea that the potato effect is purely the result of cutting out processed foods and sweets. If sweets were always a potato-effect-killer, they would have stopped the effect here. They didn’t, so they aren’t.  

Of course, we’d love to see replications from other people too. So if you’ve been on the fence, consider trying potatoes + skittles.

If so, please let us know how it goes! But it will have to be your own self-experiment, because as mentioned above, signups for the riff trial are closed. Expect a final report and a retrospective some time around January 2025.


07566174 – Potato + Dairy (ice cream)

Riff 

Potato plus a bit of dairy, ice cream for a treat

Report

Hello,

I’m emailing to share results after 6 ish weeks of potato diet. Overall very successful despite rampant cheating! I’ll be continuing for a few weeks more.

28818306 – Potatoes + Dairy + Lentils + Lettuce

Riff 

I’m trying to combine what looks like working riffs (potatoes + dairy + lentils) and add some lettuce to the mix to see if it keeps working and makes it “healthier” (at least according to my wife :-))

Report

Hi just wanted to let you know that I ended the 4 week of the potato riff trial.

It went well in the first 2 weeks, the other 2 were kind of slow, and harder to follow.

My diet consisted of a lentils burrito for breakfast (lentils flat bread + cooked lentils as filling + cheese). A mix of baked potatoes + cheese during the rest of the day. I tried to keep it mostly potatoes and use cheese for variety or as a snack.

I usually cooked 2 big batches of potatoes every week and I reheated them on a pan with a bit of olive oil.

I happened to take a blood test at the end of the diet and notice a drop in a few markers.

I’ve attached 2 pdfs. One is the most recent and another was 6 months before for comparison.

You can use them in your posts if you anonymize them.

They were translated by AI but look ok

Cheers

92679541 – Potatoes + Oil + Dairy

Riff 

My plan is potatoes + oil + dairy (mainly cream and butter)

Report

I’m stopping the diet early (after two weeks). I ended up doing a *very* loose protocol – basically potatoes + anything that would be fine on Keto (i.e. potatoes intended to be basically my only carb). As you can see from my entries, I cheated most days, typically with sweets, for which I experienced really wild cravings. I am down ~ a couple of pounds from my first weigh in.

97027526 – Potatoes plus butter, ghee, cheese, and spices

Riff 

Not 100% decided yet! Perhaps potato + butter/ghee + spices or potato + butter/ghee + cheese + spices. Planning to do this with another person in my household. We intend to do this just for 4 weeks but if it is going really well and I don’t find it difficult I may continue for another few weeks

Report

Dear Slimemold Timemold team,

August:

I’ve just found the below updates in my drafts from months ago. Not sure if it’s still interesting, but I did eat the potatoes! I ended up going back to my normal diet and I am almost back to my starting weight now. Thinking of giving it another go in September.

February:

I saw your latest potato riffs article today and when I didn’t see my own results there I realised I forgot to send you the following email almost a month ago when I completed the four weeks… So here it is:

Note from the end of the first four weeks

I have completed the four weeks!

I initially planned to do potatoes plus butter, ghee and spices but ended up adding cheese after a few days. This added a bit of interest and I think made me more likely to comply with the diet. I am exclusively eating raclette cheese (a Swiss cheese normally eaten with potatoes). The first two or three days were a bit tough, but after that I had no problems. I discovered I LOVE baked potatoes (first cooked in the microwave then finished off in the oven to crispen them up) and over 70% of my potatoes were cooked like that. After reading about the increased resistant starch in cooled potatoes I decided to cook potatoes the day before. I only managed this sometimes so about 40%-50% of potatoes were pre-cooled. At the start of the diet I ate lots of spices on my potatoes (home ground garam masala and chili flakes) but as time goes on I find myself satisfied with butter and sometimes salt as flavourings.

I am surprised that after four weeks I still really like potatoes! I’m going to continue with the potatoes for a while (probably another 2 weeks maybe another 4) and will keep using the spreadsheet in case that’s useful.

Update from 21/03/2024

I am almost at the end of 8 weeks and still going strong. I have removed the cheese because I suspected it was behind some bowl complaints. No complaints since I stopped the cheese. My diet now exclusively consists of baked potatoes, butter, salt (a few pinches once a day), pepper and sometimes garam masala. Potatoes are about 60% pre-cooled 40% freshly cooked. I’m not nearly as hungry as I used to be. 

Thanks for organising!

50108266 and 20953986 (Potatoes + Organ meat)

Riff 

Hi! 

We are planning to participate in a trial with my husband / wife. So, there will be two very similar applications. [SMTM’s note: as indeed there were!]

We want to start with the plain potato diet and then add organ-based meat to it.

Reasoning includes personal preferences and curiosity about BCAA and PUFA theories. 

Our current diet is 70% “Steak and Salad,” “Fish and Salad,” or “Plain Yogurt, Steak and Salad.” Some days, we binge on processed sugary sweets, then do steak and salad again. Our main dietary sacrifice is starch. And despite most of the time having a “colorful and diverse plate,” straight from the dietary recommendations brochure cover, we both consistently gain weight. So now we want to try to revert our diet.

We both search for dopamine in food and have difficulties fighting cravings, so as a second ingredient, we need something we will be very interested in. We had two main candidates – something sweet or something meaty. 

The results of the Potatoes + Beef riff were not good, and we already know that eating lots of beef doesn’t work for us either. So we had to find meat we like, but don’t eat often. In our case, it’s the organ-based meat. It is common in our home cultures but is absolutely not popular in the country where we live now. So, we did not eat organs and bones for a long time, but we used to eat them when we were thinner. And we really miss it, so it makes us excited. 

Regarding the PUFA theory: to be consistent, we had to decide which type of fat to use for frying the potatoes. We decided to go with butter and leave seed oils aside.

The plan is the following:

1. We start with the 2 weeks plain potato diet

    – We eat potatoes of all available types and in all forms, ad libitum

    – We season the potatoes to make them tasty. It includes adding salt, garlic, different peppers, fresh dill. If the potatoes stop being tasty, we try to add something else in controlled amounts – parsley, soy sauce etc.

    – We fry with butter, preferably ghee. We don’t cook with seed oils during the diet.

   –  We may eat restaurant fries, which probably will be cooked with seed oils, but we don’t make it the main part of our diet

    – We may eat store-bought chips, but we don’t make it the main part of our diet

2. We drink our usual amounts of water, tea, Coke Zero, and coffee, but we don’t add milk to our coffee anymore.

3. We do our cheat meals on weekend breakfasts. Usually, it’s some kind of “balanced European breakfast” – avocado, egg, toast with butter and cheese, smoked salmon, croissant, orange juice

4. We keep taking the supplements we are used to take, which are 

Wife’s case

Lion’s mane – 2500 mg

Vitamin B complex (includes 50 mcg B12)

CoQ10 – 200 mg

Liposomal vitamin C – 500 mg

Saw Palmetto – 500 mg

Myo-inositol – 1000 mg

Husband’s case

Lion’s mane – 2500 mg

Vitamin B complex (includes 50 mcg B12)

CoQ10 – 200 mg

Liposomal vitamin C – 500 mg

5. We stop taking

Omega 369 – 500 mg – Because it’s seed-oil based

Kalium-Magnesium Citraat – 270 mg – Because we increase potassium intake with the potatoes

6. We keep taking prescribed medications 

Wife: I don’t have any

Husband: Fluoxetine

7. We follow the second 2 weeks by adding the protein but trying to keep it on the low-BCAA side. It will be beef and chicken:

   – Bone broth

   – Tongue

   – Liver

   – Heart

   – Stomach

   – Intestine

   – Kidney

   – Other organs we may find in the shop

   – But not the muscle meat

8. We also intend to try to add the third component to the diet or change the component after 4 weeks, depending on the results of the first weeks.

Report

We, 50108266 and 20953986, did it. Here is our report!

TLDR

2 weeks potatoes – lost weight, but hated it

2 weeks potatoes + organs meat – lost less weight, enjoyed much more. We will keep going.

Report

We live in the Netherlands, another country of lean people (16% obesity rate) whose diet contains a significant share of bread and potatoes. The potato part of the diet was easy to organize, as there are tons of potato options in the supermarket, and french fries are available in any restaurant.  For the first week, we bought as many options as possible – different brands of potatoes sliced for fries, more starchy and less starchy potatoes for baking and boiling, and potatoes sliced and mixed with various spices. 

We ended up with a pretty stable diet. For breakfast, we ate air-fried fries. For lunch, we baked potatoes in the oven with their shells and seasoned them with salt, garlic, dill, and butter. For dinner, we baked potatoes again or boiled potatoes with the same seasoning. Usually, after dinner, we had one more snack with store-bought chips.

The first week was especially difficult, as we were constantly bloated, constipated, dehydrated, and hungry. We were eating smaller volumes than we were used to, feeling satiated by the meal’s end but also hungry shortly after. Because of our diet mood, on the first days, we were hesitant to eat more; also, despite our hunger, potatoes were not attractive enough to get up and cook some. Some nights, I was struggling to fall asleep because of growling hunger mixed with a heavy feeling of being bloated. Some nights, we were binge-eating a big pack of chips per person.

We both felt we were not losing enough weight for such a struggle. We both have experienced losing significant amounts of weight with calorie-restricted low-carb diets, and we both felt that “at that time we were losing more weight and faster.” However, I have weight records for myself for those times, and actually, weight-loss speed in absolute amounts was the same. 

The second week was easier as we found preferred options and ate more boiled potatoes. In the middle of the second week, 20953986 started to add a little bit of mayonnaise “for the taste.”  It’s an interesting choice, as he usually is a hot sauce person. Maybe mayonnaise was easier to reach, or perhaps he was attracted to protein in it. For me, 50108266, the smell of eggs in mayonnaise was extremely tempting, and I spent the whole 12th evening thinking about eggs obsessively. On the 13th day, I also accidentally felt sick at night, like I had food poisoning or a stomach bug; both are not common to me. 

On the morning of the 15th day, 20953986 almost cried over his morning potatoes because he was hungry and disgusted at the same time. 

I learned that I could not predict how much weight I was losing. I could not explain my weight fluctuations with bowel movements, water loss, water intake, or menstrual period. I also could not correlate how swollen I was with my weight. However, 20953986 sees the correlation between his bowel movements and weight. I also tried to find a correlation between weight loss and hunger and weight loss and eating processed foods. I was expecting to lose more weight after sleeping hungry, and less weight after eating a full pack of chips, but neither I nor 20953986 found such correlations for ourselves.

In the third week, we started with organs. Organ meat is not typical in Dutch culture but quite common in Turkish and Russian, so we love it and know how to cook it. We added pork liver sausage to our air-fried fries breakfast. For lunch, we usually had boiled beef tongue with boiled or baked potatoes. For dinner, we had either soup with chicken hearts, potatoes, and bone broth or fried beef liver with fries. The grilled liver was also relatively easy to find in Greek and Turkish restaurants, so we had quite a lot of it. We also tried kidneys and thymus, but we did not like them.

In the third week, our weight fluctuated in an unusual way. On the 15th day, the first day of the organ diet, I developed symptoms of an ear infection (even more unusual to me than a stomach bug) that lasted until the 17th day. On the 16th morning, I got +1 kg (2.2 lbs); on the 17th morning, my weight was the same, and after the infection symptoms were gone, my weight rapidly dropped. But the resulting weight loss in the third week was still a pitiful 0,7 kg (1.43 lbs). I assume the reason for the weight gain was an infection, but it could also be a change in the diet or a change in our cheating routine. On that day, we had our planned cheat moment, but because of how depressed 20953986 was, instead of cheat breakfast, we had cheat lunch, which, in my case, contained grilled chicken breast, bread, and yogurt mixed with spices. 

20953986 also did not lose much weight that week, but he gained weight not at the beginning of the week, like me, but on the weekend. He also had a sick moment, but it was a chronic muscular pain problem that most possibly had nothing to do with the diet and weight. 

On his rolling average graph, we see that there is no actual change in the weight loss velocity. 

The fourth week was easy and enjoyable. We never felt too hungry, did not suffer from digestion problems, and got our second-best weight loss results in the four weeks. 

The only thing that we noticed was a craving for vegetables and greens.

At the end of the report, I want to mention the cheat days. We were cheating on weekend breakfasts, as it is an important ritual for both of us. We went (except for one time that I mentioned) to the regular places where we go for breakfast; we always had several latte macchiatos and some kind of an assorted breakfast platter with greens, eggs, savory sandwiches, and pastry (you can imagine continental breakfast or Turkish breakfast). I noticed several things for myself that, however, did not work for 20953986:

  1. I was less attracted to bread and pastry. Last time, I did not touch my bread at all. This also means that I ate less for breakfast than usual. 
  2. We had two breakfasts in a row, and every Sunday, despite the cheating, I had a weight decrease, but after the second breakfast on Monday or one time on Tuesday, I had a weight increase. This pattern included even the first Monday of a diet. We started our diet on Sunday; we ate a cheat breakfast, then ate only potatoes, and my weight increased the next day.
    I wonder whether it is a coincidence, whether something I eat stimulates some weight increase, or whether it is about waking up later on the weekend. When we had a holiday during the third week, I also had a weight decrease followed by an increase, although we did not cheat that day. But the third week was a mess anyway.

Because of this observation, we want to try some experiments around it. Considering that we are limited with our habits and working week, we can’t change much, but our current intention is to keep the same diet and try different times of the day on weekends for the cheat meals, which will also lead to different cheat foods. I am open to suggestions.

54084282 – Potato, Bacon, Black Coffee, and Guinness

Riff 

I’ve recently been experimenting with potato dishes in anticipation of trying a potato diet to lose some weight I’ve gained in the past few years. I feel a diet that I could stick to for 30 days would be potato, bacon, black coffee, and Guinness. The bacon would help supplement fat and protein missing from the potatoes and reduce the need for extra seasonings. The coffee and Guinness are mostly for personal preference but also helps supplement nutrition. I plan to also use a variety of potatoes, including sweet and red with peel on.

Report

It’s now 30 days, just checking in but I plan to continue on my potato riff. I still hope to make it down to 135 lbs 🙂

I have modified from my original riff! I’d characterize my current plan as fermented food/drinks + potatoes, along with a serving or two of protein daily. It is resulting in steady weight loss while alleviating the bloating and unpleasant constipation feeling that I experienced initially.

I have lost about 5 pounds this month while feeling generally satisfied and still surprisingly not tired of potatoes. Only real remaining issue is eating out. I just cannot bring myself to order only French fries for a meal (especially around the kids). I just cheat in those situations but still manage to steadily drop weight, lol. Thanks for bringing this diet to my attention, it’s been good to me!

83842317 – Potato + Meat

Riff 

potato + meat (chicken, beef, pork, fish). I had energy on the last round, but lacked the energy to continue heavy strength training and had to give up lifting the last two weeks. I’d like to see if having meat occasionally can help with recovery and keep my strength and training regimen up while losing weight.

Report

Done.

  • This was much easier. Strength and endurance workouts were fine and I never lacked for energy. I was lifting for maintenance and ramping up endurance for a marathon in October and never had to quit a workout for lack of energy.
  • There was a tracked 38h:32m:25s, 72.53 mi, 18856 kcal of workouts across hiking, walking, running, swimming, and various cardio machines during this period.
  • I had several trips throughout the period, so sticking to it was a challenge. I made do with bags of potato chips and cans of fish from grocery stores, but not always having access to an air fryer was tricky.
  • I took cream or half-and-half when available in my 1-3 coffees per weekday when in an office (maybe maybe 12 of the total days)
  • I caught a nasty cold on the 13th that kept me bedridden and alternating between eating and sleeping for days
  • Between all the travel, it was difficult to get access to a scale, so I wound up weighing myself on five different scales when I could find one.

The convenience of eating tater tots, hash browns, chips, fries, and meat has been very easy and I’ll be sticking to it out of mostly convenience. I’ll add in vegetables for other nutrients, but psychologically I haven’t craved variety in my diet for several years, and the convenience is unbeatable. All I need is a reliable option when traveling.

22179922 – Potatoes and Cows

Riff 

I am primarily interested in learning more about how keto interacts with potatoes.  

History: About a decade ago I lost weight, and kept it off, with keto (note: a sort of meat and veg keto, elements of paleo and Mediterranean, more butter and animal fats than vegetable oils, and lots of intermittent fasting).  I felt great, and it removed the constant hunger that I didn’t even know I had (a commenter on your blog called it the Hunger).  I then gained quite a bit of weight due to a high stress situation in 2020, and for various reasons (pregnancy, breast-feeding, loss of gall-bladder) have been unwilling to go back to that diet until now.  Also my ancestors would have eaten a lot of potatoes and dairy, and it seemed to work for them.

Current situation: I need to lose 10-20 kg.  I am still breastfeeding, and thus need more nutrients (particularly protein) than average.  I also am often low on iron.  There may be another pregnancy in my future, so I would like to lose this weight fast.

Riff: I will start with potatoes, dairy, salt, and spices at libitum for two weeks (to see whether potatoes works for me, and to put the diet most likely to work up front).  I will then add in some animal products (especially fat, stock, and liver from beef, pork, lamb) for another two weeks.

After the four weeks are up, I would like to try alternating two weeks keto (as described above) with two weeks potato (potatoes + dairy + animal products) for as long as I need to (possibly two months).

If I become pregnant again, I would like to try keto + potatoes (at the same time, rather than alternating).  I’m wary of doing any extreme diet during pregnancy in case hormones/epigenetics/etc affect the baby.  However putting these two extreme diets together makes a diet that doesn’t seem extreme at all.  

Reports

First Interim Email

Hello SMTM,

Participant number: 22179922

Riff: potatoes and cows (I think I called it something else when I first

pitched it, but this name is better).

I have finished the first four weeks of my riff.  I intend to keep

going, but I’m sending you my interim report now.  I’m not sure whether

you want to publish it now, or when I finish for good, or both, or

neither, but I’m at least sending you the interim report now since I

intend to keep going for the foreseeable future.  It’s in txt format so

it’s easier for you to turn into whatever format you need, with whatever

formatting is required.

I’ve included some information in the report about my dieting history,

for context.  I’ve also included my conclusions about obesity and weight

loss in general to get a better idea of how I felt over the course of

this diet and how it shaped my opinions. Should you prefer, you may

publish my report without those sections, but I’ve included them for

context; and as a reader I’d like to read similar things from others.

First Interim Report

Participant number: 22179922

Riff: Potatoes and cows

*The Riff*

I like dairy, so wanted to do potatoes + dairy.  Aiming for potatoes garnished with dairy, rather than 50-50.  But I am currently breastfeed and thus may need more protein than usual, as well as other micronutrients, so I decided to add in animal products too.  I’ve heard rumours about too much protein, so I decided to focus on things like stock, fat, liver, and only eat flesh if I felt a craving for it.  I’ve also been reading about seed oils recently, so I decided to focus on beef and lamb (yes, I know lamb is not from a cow) rather than chicken and pork (I rarely eat pork anyway).  Since I’m allowed both butter and animal fat, there’s no point using any other sort of cooking oil.

But I also wanted to see whether potatoes would work for me at all, so I decided to start with two weeks of just potatoes and dairy, followed by two weeks of potatoes and cows.  I did not end up following this to the letter, but I decided to split this diet up into multiple levels and record each day which level I did.

0 – Potatoes only (salt and butter allowed begrudgingly)

1 – Potatoes and dairy

2 – Potatoes and non-flesh animal products (i.e. fat, stock, organ meat)

3 – Potatoes and animal products

4 – Potatoes, animal products, and fruit and vegetables.

I never reached level 4 in the first month (unless you count cheat days), but I put it in because for the next few months I want to experiment with alternating between potatoes, keto, and keto+potatoes in two week blocks.

Some Q&A about this riff:

Why now?  Baby is getting most calories from food rather than breastmilk, and I just came across the potato thing a few days ago, and I want to have another baby soon, so now’s my chance.

Why potatoes?  Preliminary results seem pretty promising.  Also I love potatoes.  Also my ancestors ate lots of potatoes so they might work well with my genome.

Why dairy?  Preliminary results seem pretty promising.  Also I love dairy.  Also my ancestors.  But also, I’ve heard good things about butter in particular as a source of fat, and I love eating potatoes with cheese and/or butter.  

Why add animal products? I need iron.  Also frying potatoes in tallow.  Also other animal nutrients.

Why not meat?  I might add meat if I feel particularly protein hungry, but preliminary results for meat seemed not great, and I mainly wanted to test potatoes, rather than “meat and potatoes”.  But someone (possibly me) should test “meat and potatoes” in the future.  Or even “meat and potatoes and veg”/”meat and 3 veg”.

Why not chicken?  Preliminary results for eggs seem bad, and also their high in lithium.  I’ve heard rumours that chicken fat inherits its omega3/6 etc from its diet, and chicken diets are probably bad, so I think chicken might be a confounder that is worth testing separately.  I’d like to test free-range vs feed lot chicken though.

Doesn’t pork have the same problems as chicken?  Yes, but I rarely eat pork as I don’t particularly like it, and I especially avoid pork fat, so I’m not particularly fussed about it.

What about fish?  I might add some fish as “meat” if I feel particularly protein hungry.  But I don’t really eat fish stock, or want to fry potatoes in fish fat, etc.

*About me*

 – I am female.  Ever since puberty I’ve needed both red meat and iron supplements to stay ahead of deficiency.  

 – I’ve always been a bit on the chubby side, with my BMI hovering at the overweight border of normal all throughout childhood.  I love food.  Food makes me feel better and I stress eat and emotional eat and eat for enjoyment and very rarely forget a meal.  (I suspect genetics makes some people feel this way about food more than others, and therefore people like me will overeat more than undereat, and thus will tend towards the overweight side of the spectrum, and will be more likely to be overweight/obese when there is an environmental issue.  Whereas my husband often forgets to eat, so that probably counteracts whatever is in our environment)

 – I need strict rules.  I don’t do well with moderation.

 – I need extrinsic motivation.  I love food and don’t particularly care about appearance, and don’t really play sport.  Being part of a study is particularly good for this.  

 – Related to the above, I am Catholic and find that I am able to “diet” during Lent in ways that I don’t have the willpower for during the rest of the year.  I’ve recently been experimenting with trying to use this to help with both moderation and motivation, e.g. only having sugar on “Feast days”.

*My weight and dieting history*

Childhood: My normal/starting adult weight is 75kg.  Both my parents have always been overweight.  We would often flip flop between lots of take-away, and a strict wholefoods/mediterranean diet.  My mother tried to be mostly low-carb, and used olive oil rather than canola/vegetable oil.  We rarely ate wheat or junk food due to a coelic in the family.  I never felt true satiety, but could feel physically full, and would also use social cues to determine when to eat or stop.  I noticed a commenter on SMTM refered to “the Hunger”, and that’s exactly what I have. Eating Chinese take-away was an occasion for bingeing.

Anecdote about “the Hunger”: As and adult, I went to the USA with my family.  I felt the Hunger stronger than ever before.  At one point we’d just finished eating lunch and my (stick-thin) sister saw an interesting restaurant and decided to get a second lunch.  I thought “Of course we could all eat a second lunch, but it’s not socially acceptable to admit that, and even less so to actually do it”.  I now understand that not everyone feels this Hunger.

First weight gain: in my third year of uni I looked in the mirror and realised I’d gained a lot of weight.  I was now 85kg.  At the time, I attributed it to following my now-husband’s diet patterns (lots of carbs, we’d often share some hot chips together for lunch, very little meat or protein) rather than my mother’s (too many carbs are bad, eat some protein with every meal).  However, having read “A Chemical Hunger”, I now see it could be due to moving house, moving daytime environment (from school to uni), the preponderance of on campus food options (pfas, seed oils), or even the increase in my wheat (glyphosate) or non-freerange chicken (antibiotics?) intake.

First weight loss (keto): I did a combination of keto and intermittent fasting.  My keto diet was basically meat+veggies, with some dairy, as opposed to what I’ve heard called “Standard American Keto”.  I never measured my ketone levels, but I determined ketosis based on how I felt, and in my opinion this was reasonably accurate.  I would generally eat one meal a day, occasionally with one snack, occasional fast for the whole day, and every two weeks I would reintroduce carbs for two weeks.  I rarely ate take-away, at mostly animal fats.  I lost 20kg in 6 months and got down to my lowest adult weight (65kg).  I very quickly gained those last 10kg back (within two weeks), and was stable at my old set point of 75kg for the next 5 years.  For the first time in my life I no longer felt the Hunger.  And even when I reintroduced carbs, I found the Hunger was still gone for the next week or so.  I felt true satiety!  And when the Hunger returned in force, I was able to kill it off with a week of keto, or stave it off with one day of keto/fasting every one to two weeks.  

But this weight loss also co-incided with another change in environment, both moving house and moving workplace/school/uni.

Second weight gain (2020): I had a combination of a long term stressor, plus some acute stress, plus some physical influences, plus the covid lockdowns, all coalesce at once, and I gained about 15kg that year.  But, having read “A Chemical Hunger”, I notice this weight gain also coincided with moving house, and a change in living arrangements (I got married), and a change in eating behaviour (I was now a short walk away from a supermarket that liked to mark down their products, so I would often go for a morning walk through the supermarket to grab a bargain, and ended up eating a lot of packaged and processed food (pfas? seed oils? glyphosate in wheat? etc).

Pregnancy etc: I was now 93kg and creeping up and up, and I became pregnant.  Suddenly I couldn’t do keto (this is debatable, but I decided to be safe in case of hormones or epigenetics) or fast any more, so I could neither arrest this upward trend nor reverse it.  Also I needed a lot of extra protein and extra nutrients (from what I understand, this is mostly for the mother’s sake, as the baby will generally steal her nutrients regardless).  Morning sickness meant I could eat only carbs, fruit, and some dairy.  I had strong cravings the whole pregnancy for carbs+dairy, and this continued into breastfeeding.  

Gall bladder: a few months after giving birth, I went to hospital and needed my gall bladder removed.  I did some research and realised that I needed the following diet for the rest of my life:

 – high fibre (to slow down digestion and soak up gall that is produced)

 – steady fat intake, so lots of small meals is better than one

 – relatively stable diet.

 – at first I thought I had to eat breakfast, but with some experimentation it seems that I can skip it as long as I’m consistent.

 – I’ve heard rumours that different fats react differently (in particular, that coconut oil isn’t digested by gall, and that olive oil feels better the next day than fish and chips grease)

These rules are at odds with my previous success at keto and one meal a day.  I was pretty scared to try anything slightly away from general medical establishment food recommendations, hesitant to try keto again, and scared to go too long without a meal, even when not hungry.  I then gained another 10kgs, and ended up just over 100kg.  

Second weight loss: I knew something had to be done, so I decided to try keto again.  I kept starting and then cheating a day or two later, so I never made it to ketosis, but it did help me to feel comfortable with keto again, even without a gall bladder.  I finally managed to reasonably consistently do keto during Lent (cheating every Sunday though), and I lost around 5kgs (from 102kg to 97kg).  Then I discovered SMTM and the potato study a few months later.  And if I can make keto+potatoes work, I can continue that through pregnancy and breastfeeding in the future.  I lost about 2kg in a month with this riff.

*The month of potatoes*

I started off with just potatoes and dairy.  I very quickly found myself eating a lot more dairy than envisioned, as a piece of cheese or a glass of milk made a good snack.  I found myself always running out of potatoes at the beginning.  Very excited, as potatoes and dairy are both delicious.  At the beginning I would often find myself too hot, and fidgety, but as time went on I felt it a little less.

I started adding animal products earlier than envisioned, at day 5.  Surprisingly, I didn’t yet have any cravings for them, but my husband wanted to feel included so I made us some sweet potatoes fried in animal fat.  I also added meat earlier than expected, on day 8, due to wanting a bit more variety in my diet rather than a craving.

My typical meals were baked potato (usually microwaved, served with cheese and sour cream), soup (potato boiled in stock with cheese, often with lemon juice and pepper added, and usually with a potassium salt mix added too), fried potatoes (either fried in animal fat or ghee, sometimes steamed or microwaved before), and cepalinai (a lithuanian dish involving grated potato, wrapped around mince, boiled, then served with sour cream, onion, and bacon).  I’d never made cepalinai before, and never did succeed perfectly, but I had a lot of fun this month trying very slight variations in the mixture to try to get them to work.  Note that steaming, rather than boiling, is a great cheat’s way of cooking cepalinai without them falling apart.

I often had a bite of my child’s food when she wanted to share with me, but I didn’t count this as cheating.  On Fridays I would eat a few bites of salmon with my potatoes.  I would generally cheat when going out, which was mainly Saturday evening and Sunday brunch.  Some days I would have a square of dark chocolate after dinner.

Early on, I tried two meals that I knew would have lots of leftovers (roast potatoes – potatoes that had been previously boiled with butter, garlic, lemon juice (I had been given lemons the day before I started this diet), herbs; and scalloped potatoes with a cream and garlic sauce).  I gained 1.3kg, which is technically within uncertainty given how much my weight can vary day to day, but it was quite disheartening and I tried to troubleshoot.  Here’s my diary entry from that day: 

> Why am I gaining weight?  Eating too much?  Do I need less variety?  Am I eating too much cheese?  Does boiling reduce potassium too much?  … I can gain/lose by up to 3kg just because (e.g. bloating, mensturation, etc), so idk.  

From this point onwards I never boiled my potatoes unless I was going to eat the boiling water too.  And I never made large oven tray meals either, or meals with garlic, because I noticed I overate those two meals.  

From my fasting days, I had a jar containing a mix of potassium salt, sodium salt, and lemon-flavoured magnesium.  The label has rubbed off and I no longer remember the quantities.  I decided to try adding this to my food in case potassium made a difference.  But I also hate the metallic taste of potassium and the weird fake lemon flavour of the magnesium, so I could only add this in small quantities, and only if I was also adding lemon juice, and practically this meant I only added it to soup.

On some days, especially day 8, I felt extremely hot and fidgety, and it was an internal heat, as though my metabolism was on fire.  I started recording my daily morning temperature after that, but there was nothing out of the ordinary there.  And on some days I was extremely cold, as though I was eating at a calorie deficit, but it was hard to say how much of that was due to the cold winter weather on those days.

Got sick around halfway through, but kept eating potatoes.  Got very little sleep towards the end and probably overate.

While the Hunger never quite went away on this diet like it did during keto, I did get very attuned to noticing a certain variation on the Hunger, which I’ll call the Addiction.  As far as I could tell, the Addiction cropped up whenever I ate seed oil (usually take-away foods like hot chips and Chinese, or packaged foods), but this could easily be confounded by pfas or some other problem.  And when it cropped up, I felt a compulsion to eat that particular food, and never felt satiated by that food, and furthermore the Addiction seemed to hang around for about 12-24hrs.  

I’ve realised that the Hunger seems to come in at least two parts, and on days when the Addiction wasn’t there I found myself occasionally feeling semi-satiated and happy to put my half-finished food away for later.  If the seed oil blogs are right, I wonder if the Addiction is direct vegetable oil metabolic harm and the non-Addiction part of the Hunger is some sort of indirect metabolic harm from vegetable oil.  Or they could be from at least two different sources of contamination etc.

I never got sick of potatoes, and in fact found a new appreciation for them.  I particularly enjoyed feeling a connection with my european ancestors.  However, towards the end I did feel a strong yearning to include other foods like onions, eggs, or a touch of flour.  This was not a craving, but because I wanted to better emulate some of these ancestral recipes.  In future I may decide to be a little more lax with things like that.  On the other hand, I never managed to eat only potatoes (and salt).  I tried eating only potatoes twice: the first time I caved and added butter at dinner, the second time I had butter with every meal and caved and added cheese and milk at dinner.  I don’t think I could do a straight potatoes diet.

*My current theory*

I read “A Chemical Hunger”, and I generally agree that there is some sort of contamination in the modern world.  Probably multiple.  But I also think some things like seed oils and HFCS may be a problem too.  It seems like certain diets (e.g. keto) may be a bit of a work-around for a broken metabolism, but I love carbs so I’d like to get to the bottom of this so I can eat carbs freely some day.  

Mainly, I think that each of these issues probably causes obesity in some people, but none of them will be the cause of obesity in everyone.  And if we remove one thing (e.g. pfas), some people will get completely better, and others will get a little bit better, and still others (hopefully very few) will have been permanently broken.  For me personally, I think seed oils are one culprit, but I think there’s at least one other that I haven’t identified yet.

The fact that semaglutide has been found to work against addiction makes me wonder if one of it’s main pathways is preventing “the Addiction”, and thus that vegetable oil (or whatever similar thing in processed food (both ultra-processed packaged food and commercial restaurant/fast food)) is a culprit for many people.

*The future*

I’m going to have a few cheat days, maybe up to a week, and then try alternating between keto and potatoes+cow every two weeks.  I may allow a few extra things like onions and eggs during the potatoes+cow phase.  Next time I pregnant, I’d like to try some version of keto+potatoes, i.e. a sort of wholefoods diet that includes milk and excludes rice and wheat, so as to be sufficiently mainstream.  I’d like to avoid vegetable oil, but that’s extremely difficult at the best of times.  I’d also like to avoid packaged and ultra-processed food, and wheat.  

Things I’d like to experiment with in the future (or see someone else try):

 – Rice (I love rice and could eat it all day)

 – Better bread (many variations, e.g. made without soy, without vegetable oil, from european wheat, etc)

 – Free range vs. cage eggs (and chickens)

 – Chicken (esp free range) vs. red meat

 – Animal products vs. animal flesh

 – Meat+veg+potato(+dairy)

 – Alternating keto and potato, or keto and potato+keto

 – Modern Catholic diet: preplan what fast (i.e. some sort of food restriction) and feast days mean, and preplan which days of the year are which (mix of long and short periods), and then follow that

 – Medieval Catholic (or Orthodox) diet: as above, using medieval rules.

 – Medieval peasant diet: as above, but with very little meat except on Sundays and feasts.

Second Report

Hello SMTM,

Here’s my next (probably final) report.  This time there is less to say, so I’ll just say it here instead of attaching it:

————————————

Participant number: 22179922

After I completed 4 weeks of potato+cows, I decided to start alternating between 2 weeks “keto” and two weeks “potato”.  

During my two weeks of keto, I tried to do something similar to ex150 from ExFatLoss.  That is, one meal containing veggies + a limited amount of protein, and as much cream as I like the rest of the time.  But because I don’t have a gall bladder, I require more fibre with my fat so I decided to add veggies or berries to the ad-lib cream.  Overall, I don’t think this worked very well.  When I exclude the initial water loss, I think I even gained weight here.  And it took about a week for my gall-bladder to adjust, so I should have chosen a longer period.  And towards the end I was craving carbs and protein and I had to switch to potatoes early.

I then intended to do a further two weeks of potato+cows, but it turned out I was pregnant.  That probably caused the protein cravings, but I don’t think it caused the weight gain.  Because I was pregnant, I decided to follow potato+cows very loosely, indulging in any cravings that came up ad lib.  However, it turned out that most of my cravings were for meat, potatoes, and dairy anyway, so I actually followed my potato riff reasonably closely.  Three common additions during this time were onions, eggs (free range), and flour (Italian to avoid glyphosate), mostly so I could follow certain potato recipes.

Overall, I didn’t seem to lose much weight in the initial 4 weeks, and to the extent that I did lose it I seemed to gain it all back in the following 4 weeks.  I also felt very tired and hungry towards the end, but it’s unclear how much of that was due to a calorie deficit and how much was due to pregnancy.  I would not attribute the weight gain to pregnancy though.  It felt a lot closer to “weight loss by calorie deficit” rather than “weight loss by not feeling hungry”, both of which I have previous experience with.

I don’t think I’d try potatoes for weight loss in the future, but I did feel pretty good on them, discovered a few new satiety-related feelings, and I now have a new-found appreciation for potatoes.  I’ve also made a big effort to avoid fast food, take-away, and packaged food, along with Australian and American wheat, and obvious sources of PFAS.  And when I do buy pre-prepared food, I do my best to avoid fried food.  I’m sure it’s healthier, but I’m yet to see an effect on my weight yet.

I will continue eating this way for the foreseeable future, but I don’t think I’ll fill in the spreadsheet – I’ve already noticed I’m putting in a lot less information than in the first month.

And I still haven’t managed to properly make cepelinai.

59960254 – Potatoes with Fire in a Bottle Characteristics

Riff 

4 weeks. I am planning on incorporating the general idea/outlook of work like Fire in a bottle. So potatoes and a small amount of fat from sources that are not seed oils. Butter, tallow, coconut, cacao, etc.

Report

So my protocol was potato diet, low fat, low protein in the spirit of Brad Marshall’s “Fire in a Bottle” blog. So that meant the fat was generally saturated, and sources high in stearic acid. Fruit and honey were permissible, as well as dates for an evening sweet treat, or high cacao % dark chocolate. The one corner I cut on this was to frequently use this chili oil ( https://xiankits.com/products/xff-chili-oil-crisps-jar?Size=8oz ) to make the meals more palatable. In the spirit of FiaB this should be off limits because I’m sure the oil they’re using is some sort of seed oil but… can’t win them all.

For potatoes I tried a range of different styles, at first doing separate batches of regular and sweet, so that I had options. Eventually found I really enjoyed the yellow potatoes from Lidl and just make that. For prep/cooking I peel, boil, and mash all of them. At first I was weighing and tracking calories and titrating the amount of fat added to keep it below 10% of calories. After a week or 2 of this I got lazy and just eyeballed it. I experimented with all manner of combinations when eating. I found sweet potatoes often didn’t require the addition of anything beyond salt and pepper. Regular potatoes were eaten with various combinations of: butter, stearic enhanced butter (as Brad describes on his blog), chili oil, beef tallow, cacao butter, beef bone broth, honey, powdered glycine, and maybe something else I’m forgetting. 

I found the diet reasonably easy to stick to, since I wasn’t eating strictly potatoes and could vary what I put in them. One concept that Brad has talked about is the idea that saturated fat causes a feeling of satiety much quicker than PUFA and why, down to a mitochondrial level, that might be. I really buy that argument now after the last several months. The speed and intensity of satiety I get when using tallow or cacao butter is a lot. I found my perception of hunger changed whenver I had a good stretch of following the diet strictly. I wouldn’t really feel actaul hunger, I would just at some point realize I was daydreaming about how good an entire pizza would be, or a steak, or piece of cake, whatever, and know that meant I was hungry. 

Any time I’ve restarted the diet after a cheat day I find it takes at least a day to feel the effects kick in. Between potato diet and not drinking (which is still kinda a new thing for me) I find I wake up early and have good energy throughout the day. I’ve experimented with eating early in the morning to kickstart metabolism, another thing I believe I’ve heard Brad talk about, and at the other end of the spectrum waiting till at least noon or later to actually eat a substantial meal. The second option is more fun mentally because the morning fast allows me to log a lower weight for the day, and I’ll take any psychological trick that works. I found blood pressure improved pretty quickly with some weight loss and a few days into potato diet. Blood glucose was less quick to make changes, but perhaps I need to lose more weight.

I often cheated when going out to dinner with the wife, since in my mind eating fries in a restaurant is also a bad option due to the frying oil, so in those situations I just went with the flow and ordered what I wanted. I found between weight and waistline I could see some sort of progress near daily, however that progress would be quickly and temporarily undone by a cheat day or meal. Every cheat was reversed by getting back on the diet, but conversely, you could say as soon as I stopped the restrictive diet I immediately started reverting to the mean, which for me seems to be over 220. 

I only ended up losing 10# during the month in part because of cheat meals, with a few days of travel, and my favorite cat getting sick at the 3 week mark, which threw everything out of whack for the 2 weeks that he was ill before we had to put him down. Since completing the month I’ve tried to stay on the diet however it’s summer time and there’s tons of plans and it’s hard not to cheat when out and about.

My interpretation of Brad and others work is that the increased PUFA in diet throws off a variety of mechanisms that disable or alter the lipostat and cause weight gain. If Brad is right then this is in part because the body normally sees PUFA as a sign of scarcity and depresses metabolism as part of a survival mechanism. My understanding of all that is that in theory if I could purge the excess PUFA from body fat, which would likely also mean losing quite a bit more weight, that maybe then I wouldn’t so immediately start putting weight back on when I stop eating potato diet.

At time of writing I’m at 213, up from a low of 207 after a week and a few days of being off diet. Will be interesting to see how long it takes to get back to 207 and make a new low. I am having a hard time of breaking and staying under 210, and I have not weighed less than 200 in over a decade. My goal weight is still < 180, and I plan to evaluate how much further to go when I get to that point. And while this has not been as immediate a change as I’d like, I am still 20# lighter than my heaviest weight.

Also today I shared a different version of the potato diet chart/vitals with you. I don’t love the horizontal scroll to fill in the info. Will be continuing on with the V2 I shared. This was a kinda free form rambling recollection of the experience. I should have done it sooner after the completion of 1 month but ya know, was dealing with the cat and life in general. Please hit me up with any followups as needed.

95078099 – Potatoes + Soy + Plain Vegan Chocolate

Riff 

My riff is potato + soy products + chocolate! Sounds delicious, and will give me plenty of protein.

My main hypothesis for why the potato diet works is that it’s relatively bland, leading to less calorie intake. My chosen riff will hopefully not be very bland, though, and if it works, would make my hypothesis seem less likely to me.

Note that my starting weight is quite low, with a BMI of ~20. This is the result of a long, hard calorie restriction. My personal aim is not to lose weight, but to keep the weight down. If I stay at the same weight, and not drift up by a few pounds, I’d consider that a success!

I participated in the half-tato trial last year (participant ID 81471891), with a highly calorie-controlled approach, and I didn’t see a significant difference in weight loss speed between the baseline weeks and the potato weeks. This time, I plan to not count calories or track what I eat, but just to eat what I feel like, within the constraints of my riff.

Report

Hey SNTM 🙂

I finished my “potatos + soy products + plain vegan chocolate” riff! 

Found it pretty enjoyable! I stuck to my riff very consistently, and didn’t break the diet.

– Potatos: Most of the time, I microwaved them, which I found extremely convenient! But I also ate them baked, fried, mashed, and as soup. I also occasionally ate french fries, potato dumplings, and store-bought hash browns. Once, I tried making “potato cookies” from potato starch.

– Soy products: This included soy milk, soy yoghurt, soy-based cream, lots of tofu, fermented tofu, tempeh, some soy-based meat substitutes, soy flakes, and soy flour. I was really happy with the variety here!

– Chocolate: I restricted myself to plain, dark, vegan chocolate, so I wouldn’t over-indulge. But I didn’t hold back here, and ate as much chocolate as I wanted. In the end, I was a bit bored by plain supermarket chocolate. I also put cocoa powder into my soy milk sometimes.

– Oil: This was allowed per the base protocol. I mostly had canola oil, olive oil, coconut oil, and — of course — soybean oil.

– Spices: A per protocol I also added spices to my food: Salt and pepper, herbs, garlic and onion powder, chili and paprika powder.

– Sugar: On two days, I made caramelized potatos, and some of the soy milk and soy yoghurt I ate had sugar in it.

So, what were the outcomes? It is important to mention that, because of my already low starting weight, my goal was not weight loss, bug weight maintenance. Between the first and the last measurement over the course of the four weeks, I lost 0.7 kg (1.5 lbs). However, as weight measurements have a high degree of noise to them, looking at a moving average of the data seems more meaningful.

This becomes especially clear when zooming out. I have *a lot* of data on my weight, and attached some graphs: Of the last two months, of the last 1.5 years, and of all data I have (12 years). As you can see, I did a calorie restriction diet for most of 2023, where I ate 1200-1800 kcal per day. Now, I’m trying to stay inside the 64-67 kg range by resuming that restriction once I hit the upper boundary of that range, until I hit the lower boundary again.

I started the potato diet immediately after such a calorie restriction phase. This way, I could compare how effective it would be in keeping my weight down. Overall, in the moving average, it looks like I gained about 1 kg of weight during the month. This seems typical for a phase where I’m not counting calories. So, for myself, and for the purpose of keeping my weight down, I’d consider my potato riff ineffective.

Finally, here are some suggestions for how I think you could improve your approach:

– Ask people to track their weight for one additional week before and after the potato period, to be able to build better moving averages, and to see how starting/stopping eating potatoes affects the weight.

– Have participants fill out a survey at the end of the four weeks, asking for more data. Questions like “How many meals were deep-fried potatoes?”, “What total volume of oil did you consume?” or “What food did you miss most?”

– Do yearly follow-up surveys with all participants (of all previous trials)! Ask for current weight, their current potato consumption, and other dieting experiences. This would allow you to see the long-term effects of the potato intervention.

Thanks again for organizing!

UPDATE from 22293376 – Potatoes + Skittles

Previously 

Update

I have a followup with results from a second round to share – feel free to post it if you want to.

It’s me, Skittles guy* again. I’m back to report on my second round of the potato diet. After my successful first attempt in January, I decided to give it another go this summer.

Quick Recap of Round One (January):

– Duration: 4 weeks

– Weight loss: 12 pounds (187 to 175 lbs)

– Protocol: Potatoes, fats, and Skittles (consumed in moderation)

The Interim Period:

After the initial success, I maintained my weight without much effort. However, by June-July, I noticed the scale creeping above 175 lbs, accompanied by some compulsive eating behaviors. So, I broke out the potato peeler once again…

Round Two (July 22nd – August 17th):

– Starting weight: 176 lbs

– Ending weight: 166.4 lbs 

Modified Protocol:

This time, I allowed myself the following foods ad libitum:

– Butter and oil

– Sweet Potatoes

– Low-calorie vegetables (onions, peppers, broccoli, green chile, etc.)

– Skittles (in moderation)

Additional Factors:

– I’m in the midst of training for an Ultramarathon and averaged ~30 miles of running per week

– Allowed fresh fruit as a treat after runs of 2 hours or longer (4-5 times during the diet period)

– One cheat meal after a particularly long run

The Experience:

While not quite as enjoyable as the winter edition (hot potatoes are probably just less appealing in the summer?), the diet was still effective and compliance was relatively easy. Hash browns and mashed potatoes were my go-to meals, often with generous helpings of green chile. I had no particular difficulty running, and my estimated VO2Max (per Apple Watch) improved from 43.5 to 45.

Key Takeaways:

1. The potato diet once again proved effective, even at a lower starting weight.

2. Adding other vegetables was not incompatible with weight loss.

2. The diet is compatible with endurance training, supporting both weight loss and performance improvement.

The potato diet has been a game changer for me. It’s a real psychological comfort to know that I can drop weight (or even just reset my eating behaviors) with a simple protocol that doesn’t require a great deal of mental effort.

* I generally didn’t eat more than 20-30 skittles a day, and sometimes none. I don’t really recommend eating skittles-only meals but you do you!

Philosophical Transactions: AS on Potatoes-By-Default (Plus Sauce)

Previous Philosophical Transactions:

This account has been lightly edited for clarity, but what appears below is otherwise the original report as we received it. 


From April 21 of this year until today (August 5), I’ve been on a potatoes-by-default diet. This was inspired by the email by M (Philosophical Transactions: M’s Experience with Potatoes-by-Default). In that time, I went from a weight of 173.0 pounds to a weight of 155.4. I’m giving myself a slight handicap, because I actually started the diet about two weeks earlier and my weight was ~180, but I didn’t track my meals or get a digital scale until the 21st and my analog scale was unreliable. Depending on how robust you want to be about it, I’ve lost 17 or 24 pounds in 107 or 121 days. About half of that weight loss was concentrated in the first few weeks, but I kept it off and continued losing over the rest of the diet period.

The most interesting thing I have to say about this is that I have nothing interesting to say. My experience matches what I expected from reading this blog and other sources. I’ve lost weight, and noticed no adverse health effects. That made me almost not want to share here, but it’s important to share replications!

The Details

Here are the eccentricities of my particular case:

1. The diet variation I chose. 

I chose “potatoes by default” because I was interested in testing it, and because my social life puts me in group meal settings regularly. And then I added sauce because I had some sauce in the fridge I was hoping to use up. Initially I was going to discontinue the sauce after finishing it up, but I realized it wasn’t adding very many calories and I was curious whether it would affect the diet. My usual meal was a bowl of potatoes with roughly 2 tablespoons of sauce for dipping.

My favorite sauces after four months include the Zesty Secret Sauce by Marie’s, the Creamy Buffalo Sauce by Sweet Baby Ray’s, and the Gold BBQ Sauce by Kinder’s. Sometimes I would add some everything bagel seasoning and melted butter to the buffalo sauce – absolutely amazing!

One question discussed on the blog has been whether some ingredient serves as a blocker, and these sauces contained a whole lot of supposed blockers, which I think is interesting data. The percent of my meals with/without potatoes was inconsistent over the course of the diet, but sauce with potatoes was a constant, so if there’s a complete potato-diet-effect blocker, it wasn’t in the sauces.

I cooked the potatoes by cutting off the skin, cutting them in half or thirds depending on the size, and baking them in the oven on parchment paper at 425 for around 70 minutes. Potato varieties used were mostly russet and gold, sometimes red, and “baby” varieties if they were on sale.

The rest of my diet was very standard – all the normal-American-diet ingredients that might be blockers were involved, and there was no particular portion control beyond not eating when I was full.

2. Exercise.

I don’t believe exercise played a substantial role in the weight loss, but I had two exercise habits going on during this experiment and I did lose weight, so it’s worth reporting on them.

First, I walked a minimum of 10,000 steps each day, although that actually undersells the average (15,313).

Second, roughly 10 times during the experiment period, I played dance video games (DDR or Just Dance) for a minimum of 2 hours at a relatively intense difficulty mode. These mostly happened in the first two months, and were discontinued for personal reasons and not for diet or health-related reasons.

“I Could Never Do That,” Said The Person Who Never Tried

Some friends I discussed this diet with said they were interested, but could never do it, because they get cravings for specific foods when they’re hungry. I find this absolutely unpersuasive. The rules I followed let me have snacks when I got cravings; I still lost weight, and the cravings were less common than before the potato diet.

Some people in previous experiments writing on this blog noted that their desire to have junk food largely subsided while in “potato mode”. It was pretty easy for me to control what I ate at home. But sometimes I would be outside the house, and I would be a little bit hungry and get a small meal at a restaurant, and then I was in trouble! Because if I ate something small, I suddenly found myself hungry for dessert too. But if I didn’t eat out, and I went about my day, I would be perfectly happy not following that impulse. 

At any rate, if you’re going to follow any diet, potato dieting is about as close as a diet can be to Pareto optimal: (e.g. it’s better in every possible way than any diet you compare it to)

  • It’s easy to do. The rules are simpler than any other diet; the shopping is simpler; the meal prep is simpler.
  • It’s easy to stick to; it’s the only diet I’ve ever kept for more than a week. My experience with other diets is that you are constantly thinking about the food and fighting cravings for other food. For some reason, a potato diet doesn’t create that for me, especially with the leniency of “-by-default.”
  • It’s less expensive than any other diet. I spent roughly $500 a month less on groceries over the period, despite eating the same proportion of my meals at home.

No Grand Conclusion

Ultimately, this is an N=1 replication. There were times when I ate better and times when I ate worse. I didn’t always lose weight when I was having non-potato meals, but if I gained weight (e.g. on travel) I would quickly lose it again when going back to potatoes. This feels like the “lipostat” hypothesis to me; eating a lot of potatoes did something to make my set point weight lower than it otherwise would be.

I’m happy to have lost weight and even happier to be able to provide a tiny bit more data in support of the potato diet. 

Chart created by SMTM from data provided by AS

Lithium Hypothesis of Obesity: Recap

Imagine you’re us. You’re looking into the idea that the obesity epidemic is caused, in part or in whole, by some kind of environmental contaminant. The idea already seems pretty strong, but you want to narrow it down to some specific contaminants that might be to blame, so you start putting together a list.

You happen to be aware of a long-running literature that finds correlations between trace levels of lithium in groundwater and public health outcomes, things like lower rates of crime, suicide, and dementia, and decreased mental hospital admissions (meta-analysis, meta-analysis, meta-analysis). 

You also know that when lithium is prescribed as a treatment for conditions like bipolar disorder, people often gain weight as a side effect. Based on these two facts alone — lithium causes weight gain at clinical doses, and some clinical effects seem to appear with long-term trace exposure — lithium already seems like the kind of thing that might cause obesity. You add it to the list. 

Lots of contaminants on the list don’t survive your scrutiny. When you look into glyphosate (the weed-killing chemical in Roundup), you find lots of evidence against it, and you come away feeling pretty strongly that glyphosate doesn’t cause obesity. Same thing when you look at seed oils.

But the case for lithium keeps getting stronger the longer you look.

You already knew that lithium can cause weight gain at clinical doses, and you know about the literature connecting trace levels of lithium in groundwater to lower rates of things like suicide and homicide rates, suggesting that even the trace levels found in drinking water can have behavioral effects, maybe because of accumulation from long-term exposure. On top of that, you discover that there is one randomized controlled trial examining the effects of trace amounts of lithium, which found that a dose of only 0.4 mg per day of lithium led to reduced aggression, compared to placebo, in a group of former drug users. 

You find that many of the professions that are unusually obese — like firefighters, truck drivers, and vehicle mechanics — work closely with heavy machinery, including trucks and cars, that are lubricated with lithium grease. And you notice that the Middle East is one of the most obese regions in the world. This potentially fits because they get a lot of their drinking water from desalinated seawater, which may contain relatively high levels of lithium. And because (as you will later learn) fossil fuel prospecting, especially from arid regions, tends to cause a lot of lithium contamination.

None of this is conclusive, but it seems promising. You start putting out the series A Chemical Hunger, with lithium as one of your three examples of chemicals that might be causing obesity.

Among other things, this leads to some discussion on Reddit. People raise such good points that you decide to review some of their comments in an interlude to the series. There’s a lot worth considering here, but the highlight ends up being a point from u/evocomp, who says:

The famous Pima Indians of Arizona had a tenfold increase in diabetes from 1937 to the 1950s, and then became the most obese population of the world at that time, long before 1980s. Mexican Pimas followed the trend when they modernized too. 

This is an excellent point. Sure enough, the Pima in the Gila River Valley of Arizona were unusually obese and had “the highest prevalence of diabetes ever recorded”, way back before the general obesity rate had even broken 10%. 

This seems like a real blow to the lithium hypothesis — unless, of course, the Pima were exposed to unusually high levels of lithium way before everyone else.

Turns out, the Pima were exposed to unusually high levels of lithium way before everyone else. For starters, you find this report which says, “In the Gila River Valley, deep petroleum exploration boreholes were drilled during the early 1900’s through the thick layers of gypsum and salty clay found throughout the valley. Although oil was not found, salt brines are now discharging to the land surface through improperly sealed abandoned boreholes, and the local water quality has been degraded.” The report also notes that “lithium is found in the groundwater of the Gila Valley near Safford.” You also find this USGS report, which says a Wolfberry plant “was sampled on lands inhabited by the Pima Indians in Arizona; it contained 1,120 ppm lithium in the dry weight of the plant.” This is an extremely high concentration compared to other plants. 

Another USGS report says, “Sievers and Cannon (1974) expressed concern for the health problem of Pima Indians living on the Gila River Indian Reservation in central Arizona because of the anomalously high lithium content in water and in certain of their homegrown foods.”

You track down Sievers & Cannon for more detail. Sure enough, you find that the average concentration of lithium in American municipal waters in 1970 was about 2 ng/mL, while the average concentration of lithium in the water of the Gila River Indian Reservation was about 100 ng/mL, around 50 times higher. Sievers & Cannon also say:

It is tempting to postulate that the lithium intake of Pimas may relate 1) to apparent tranquility and rarity of duodenal ulcer and 2) to relative physical inactivity and high rates of obesity and diabetes mellitus.

This couldn’t possibly have been said with the goal of explaining the obesity epidemic, because the obesity epidemic didn’t exist in the early 1970s when the quote was written. Sievers & Cannon had no idea the obesity epidemic was coming. It was a neutral observation.

If you had to point to some moment as the one we started to believe in the lithium hypothesis, this would be it.

It’s easy enough to come up with a theory that fits all the evidence you’re working with. It’s hard to make a theory that will fit the evidence you’re unaware of. The real test of a theory happens when it comes in contact with something new and relevant. The hypothesis that lithium is responsible for the obesity epidemic makes two predictions (with some allowance for reality being very weird): If some group was exposed to high levels of lithium earlier than everyone else, that group should become especially obese before everyone else did. And conversely, if there’s a group that became unusually obese before everyone else did, that group was probably exposed to unusually high levels of lithium early on. The Pima fulfill these predictions.

As you discover more about the lithium hypothesis, you add more interludes to the series. In the first interlude, you talk more about the possible sources of lithium contamination, like lithium grease, desalinated seawater, and the enormous spills that are a byproduct of fossil fuel prospecting. You also provide a close read of the paper by Sievers & Cannon. 

In the second interlude, you take a look at the idea that modern people might be getting exposed to more lithium as a result of drinking from deeper wells made possible by better drilling techniques, and you start making some international comparisons.  

Then you decide to try something a little silly. You happened to find a list of the most and least obese cities and communities in America, based on data from Gallup. You think it would be kind of funny to go through each of the cities and communities on the list, and see if you can find out how much lithium is in their drinking water.

This really seems like a long shot. Most cities don’t track the lithium levels in their drinking water, and even if the lithium hypothesis is entirely correct, even if you were able to find some measurements, it’s not clear that the data would show a clear relationship. After all, communities can have more than one source of drinking water, and drinking water isn’t people’s only source of exposure. 

But the project unexpectedly turns out to be a huge success. You discover that the leanest communities tend to get their water from isolated reservoirs or pristine mountain snowmelt. Sometimes you can even find official measurements that confirm low concentrations of lithium. The most obese communities, meanwhile, tend to be drawing from aquifers with high levels of lithium, or directly downstream of coal ash ponds that are confirmed to be leaching lithium into the groundwater, or downstream of a lithium grease plant that recently exploded.   

All this seems like pretty strong evidence in favor of the lithium hypothesis. A critic would have to argue that unusually obese cities just happen to be downstream from lithium grease plants that experience catastrophic failures. This happened not once, but twice. What are the odds of that, exactly?

A few months later, you get an email from JP Callaghan, an MD/PhD student at a large Northeast research university and specialist in protein statistical mechanics, modeling, and lithium pharmacokinetics. It’s hard to briefly sum up this wide-ranging conversation, but JP agrees that the lithium hypothesis is plausible and discusses some perspectives like bolus-dose exposure and multiple-compartment models that, taken together, suggest that if you’re exposed to small doses over a long enough span, it might even be possible to end up with internal lithium levels as high as those achieved with clinical treatment. 

This still assumes that to gain weight, you need to end up with a clinical-level dose in your brain. But the trace exposure literature makes you think that even small doses have some effects. To test this, you survey people who take much smaller doses of lithium as a nootropic, and find that people who take doses as small as 1 mg/day report feeling all kinds of different effects, some of them quite negative. This suggests you may not need big, clinical doses of 50+ mg/day to gain weight, especially if you are exposed to low doses for a very long time. 

Of course, 1 mg/day is still more lithium than most people are getting from their water. But you know that people get at least some lithium from their food. Remember how the Pima were eating wolfberries that contained 1,120 ppm lithium, which works out to like 15 mg per tablespoon of wolfberry jam? 

You wonder how modern food compares, so you do a literature review. You find good evidence that there’s lithium in modern food, and especially high concentrations in certain foods like meat and eggs. You do another literature review looking at the fact that different sources report very different concentrations of lithium in modern foods. You find that the different papers use different analytical techniques, which may explain why they get such different results.

You test this idea by running an actual study to compare the different analytical techniques. Lo and behold, you find that exactly as you predicted, some techniques almost never detect any lithium in food, while other techniques detect it easily. The second set of techniques are almost certainly the more accurate ones, since they give consistently different readings for different foods, while the other techniques indiscriminately return almost nothing but zeroes. 

Looking at the results themselves, you see that some of the foods you tested contain markedly high levels of lithium. In this sample, the highest levels were detected in ground beef (up to 5.8 mg/kg lithium), corn syrup (up to 8.1 mg/kg lithium), goji berries (up to 14.8 mg/kg lithium), and eggs (up to 15.8 mg/kg lithium).

You decide to do a followup study to take a closer look at those eggs. The results confirm your original findings — nearly all the samples contain detectable levels of lithium, and around 60% of samples contain more than 1 mg/kg lithium (fresh weight). As before, the egg samples with the highest concentrations of lithium contain just over 15 mg/kg in the fresh weight. 

Another hint is that high enough doses of potassium seem to sometimes cause weight loss (though perhaps only under just the right circumstances). People clearly lose weight on the potato diet, and certainly the potato diet provides huge doses of potassium. On top of that, people who took small doses of potassium in solution lost a small but statistically significant amount of weight. And there are the case studies from Krinn, who lost a lot of weight while supplementing potassium, and from Alex C., who lost a smaller but appreciable amount. 

This also seems like some evidence for the lithium hypothesis. Potassium and lithium are both alkali metals, and it’s already well-established that sodium interferes with lithium kinetics in the body, so much so that going on a low-sodium diet while taking clinical doses of lithium can be very dangerous. It’s plausible that potassium has similar interactions.  

Correlational Analysis

People often ask us, what’s the correlation between obesity and lithium in drinking water? Honestly, we find this question a little confusing. 

First of all, everyone knows that correlation doesn’t imply causation. If you discovered a correlation between lithium in town drinking water and obesity in those towns, that would be slightly more evidence that lithium causes obesity, but by itself a correlation isn’t very strong evidence of a causal relationship.

Second, as we described in Section IV of A Chemical Hunger, a small correlation, or even no correlation at all, isn’t evidence of no relationship. Even when there’s a real relationship between two things, there are lots of things that can make it look like there’s no correlation; one example is that looking at a truncated range almost always makes a correlation look smaller than it really is. If you were to look at correlations in lithium exposure, you should expect to be looking at a somewhat truncated range, so the correlation in the data would be smaller than the real relationship, which could be misleading. 

This is why we don’t really care about the correlation, because it couldn’t clear things up one way or another. A strong correlation between lithium in water and obesity rates wouldn’t be particularly convincing evidence in favor of the hypothesis. And a weak correlation, or even no correlation, wouldn’t be particularly convincing evidence against. Since it doesn’t clarify either way, you can see why we think that going after these data would be a waste of time. 

What would be convincing is experimental evidence, if we could get it. (Though this isn’t always possible; for example, the smoking-lung cancer relationship was established without any human experiments.) We don’t understand why correlation comes up so often. People should remember their hierarchy of evidence.

In general we think this question reveals a misunderstanding about what correlation really is. A correlation is just a mathematical way of describing a relationship, and not even a very sophisticated one. The relationship is what we’re really interested in, and we already have good reason to believe that this relationship is pretty strong — all the evidence we laid out above. In our first post on lithium, in our second post on lithium, in our post on groundwater contamination and historical/international levels, and in our post looking at the fattest and leanest communities in America, we very reliably found that places exposed to high levels of lithium had high rates of obesity, and places exposed to low levels of lithium had low rates of obesity. This is strong evidence for a relationship, even if that relationship can’t immediately be expressed as a correlation. 

All this to say, we can give you a correlation coefficient, but we don’t want you to take it very seriously. It does (spoiler) come out in favor of the hypothesis that lithium exposure causes obesity. However, for all the reasons we outlined above, it is not actually strong additional evidence, just one more small item to add to the pile. 

Yes, it is a strong positive correlation. No, that is not conclusive, you need to weigh it in the balance with all the other evidence. Do not turn off your brain when you see the scatterplots. 

To calculate a correlation coefficient, you need cases where you can find a number for both the obesity rate, and for lithium exposure. In many cases we can’t get one of these numbers (how obese was Texas in 1970? no one knows) or can’t get a specific number, even though observations are in line with the theory (drinking water in Chilean towns can contain up to 700 ng/mL lithium, but how much is it on average?). 

But when we look at the 15 cases where we can give specific values to both variables (the American cities of Denver, San Jose, Barnstable, Miami, DC, McAllen, and San Antonio circa 2010-2020; plus measurements from Greece, Italy, Denmark, Austria, Kyushu Japan, 1964 America, 2021 America, and the Pima in 1973), the scatterplot looks like this: 

That correlation is r(13) = 0.744, p = 0.002, with a 95 percent confidence interval of [0.374, 0.910]. 

The shape is pretty reminiscent of a standard dose-response curve, but it could also indicate a logarithmic relationship; if you log-transform the lithium dosage, it looks very linear:

That correlation is r(13) = 0.732, p = 0.002, 95 percent confidence interval [0.351, 0.905]. 

This can’t be cherrypicked because those are all 15 cases we are aware of where we have a measurement for both the obesity rate and the level of lithium in local drinking water. If you are aware of other cases, let us know and we will add them to the scatterplot.

There are only 15 datapoints. But at the same time, the correlation is clearly significant, p = .002, even with different models.

Pace Deniers 

Some people seem to think we have an axe to grind about lithium, but we’re not sure where this perception came from. At the start we took lithium no more seriously than any other candidate. Over time, we found the evidence compelling, and now we think the case in favor of lithium is quite strong. This is all very carefully documented in A Chemical Hunger and our posts ever since. You can see every step of the process. 

Clinical doses of lithium cause weight gain. Not for everyone, but it’s a known side effect. Many effects of lithium probably kick in at trace doses, especially when exposure is long-term. This is probably because lithium accumulates in the body, in the thyroid and/or brain (though possibly somewhere else, like the bones). 

Lithium levels in US drinking water have been increasing for at least 60 years. We know where it’s coming from: increasing use of lithium grease, from industrial applications, and from contamination from fossil fuel prospecting, which produces brines known to be enormously rich in lithium. 

Populations that were exposed to modern levels of lithium in their drinking water decades before everyone else had modern levels of obesity decades before everyone else. Many of the professions that are especially obese are professions that are regularly exposed to lithium grease. 

Most of the leanest communities in America are places where lithium levels in the drinking water are either plausibly low given circumstances (e.g. they get their water directly from pristine snowmelt) or confirmed low by measurement. Most of the heaviest communities in America are places where lithium levels in the drinking water are either confirmed high by measurement or plausibly high given circumstances (e.g. they are directly downstream from a lithium grease plant that recently exploded).

It would be hard for this argument to be any simpler. Honestly, we keep feeling like we’re in the mental gymnastics meme: 

We couldn’t fill out the other half of the meme because we honestly can’t tell what deniers are thinking? If you are a lithium denier, please fill out the other half and @ us on twitter.

Lithium Hypothesis for Dummies

To help make this discussion easier, in the following sections we break down the argument in favor of the lithium hypothesis piece by piece.

We invite people to dispute this case. It would be great to hear counterarguments! 

We want to make it REALLY EASY for people to engage with the hypothesis, which is why we went to the trouble of writing this post. 

However, we have conditions.

If you want to argue, we charge you to either: 1) make the case that these premises are wrong, or 2) make the case that the inferences don’t follow from the premises. 

Anything else is pointless griping, and shows a serious lack of reading comprehension, to respond to a hallucinated version of the hypothesis rather than to what we have actually written. We won’t respond to such “arguments”. If we haven’t responded to you in the past, it’s because you displayed reading comprehension levels so low that we couldn’t find a productive way to engage.

As Zhuangzi (Kjellberg translation, p. 218) explains: 

Making a point to show that a point is not a point is not as good as making a nonpoint to show that a point is not a point. Using a horse to show that a horse is not a horse is not as good as using a nonhorse to show that a horse is not a horse. Heaven and earth are one point, the ten thousand things are one horse.

Doses

For background, let’s talk about lithium doses. 

In clinical settings, lithium is usually prescribed as lithium carbonate, and doses are given in milligrams (mg) lithium carbonate. However, lithium carbonate is 81.3% carbonate and only 18.7% elemental lithium, so the dose of lithium is much lower than the prescribed dose. For example, if you are prescribed 600 mg of lithium 2 times a day, that’s 1200 mg of lithium carbonate, which works out to about 224 mg of elemental lithium. 

To keep things standard, and to focus on the actual effective dose, numbers from here on are always elemental lithium. 

  • Clinical doses of lithium are usually between 336 mg/day and 56 mg/day. However, in rare cases lithium is prescribed at doses as low as 28 mg/day (e.g. here and here), suggesting there may be therapeutic effects at doses this low. 
  • Doses between 50 mg/day and 1 mg/day we will refer to as subclinical doses, since they are smaller than the usual clinical dose, but still appreciable amounts.  
  • Doses of less than 1 mg/day will be called trace doses, since you are unlikely to get more than this from your drinking water alone.

Premises

To the best of our knowledge, the following premises are all well-supported. However, some of these premises have more evidence behind them than others.  

Premises about Effects and Doses of Lithium

Premises about Lithium Contamination and Exposure

Premises about the Obesity Epidemic

  • O1: Some professions are much more obese than others. For example, the Washington State Department of Labor and Industries survey of more than 37,000 workers found that truck drivers were the most obese group of all, at 38.6%, and mechanics were #5 at 28.9% obese, while only 20.1% of food preparation workers were obese, and only 19.9% of construction workers. Another source, the National Health Interview Survey Data, (2004-2011) found that motor vehicle operators, health care support workers, transportation and material moving workers, protective service workers, and “other construction and related workers” had some of the highest rates of obesity.
  • O2: The Pima people, sometimes called Pima Indians, are a group of Native Americans from the area that is now southern Arizona and northwestern Mexico. In the United States, they are particularly associated with the Gila River Valley. The Pima seem to have had normal rates of diabetes and obesity in 1937, but by 1950 rates of both had increased enormously, and by 1965 the Arizona Pima Indians had “the highest prevalence of diabetes ever recorded.” 
  • O3: In the early 1970s, Sievers & Cannon found that the median lithium level in the Pima’s drinking water was around 100 ng/mL, 50 times higher than the median level of lithium in US public water supplies at the time, which was just 2.0 ng/mL
  • O4: In addition, Sievers & Cannon found an “extraordinary lithium content of 1120 ppm” in the local wolfberries, which the Pima “used occasionally for jelly”.
  • O5: Lithium contamination in the Gila River Valley likely came from fossil fuel prospecting. This report says, “In the Gila River Valley, deep petroleum exploration boreholes were drilled during the early 1900’s through the thick layers of gypsum and salty clay found throughout the valley. Although oil was not found, salt brines are now discharging to the land surface through improperly sealed abandoned boreholes, and the local water quality has been degraded.”

Premises about Lithium Concentration in Food

Primary Inferences

  • K1 – From D1, D3: Some of the known effects of lithium that appear when someone takes clinical doses also kick in at subclinical doses.
  • K2 – From D1, D4, D5, O3: Some of the known effects of lithium that appear when someone takes clinical doses also kick in at trace doses.
  • K3 – From C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, O3, O5: Lithium contamination in the United States has increased since 1962 as a result of human activity, especially fossil fuel prospecting.
  • K4 – From F1, F2, F3, C11, O3, O4: Lithium concentrates in certain foods.
  • K5 – From O1, O2, O3, O4, O5, C4: Specific populations who have been exposed to high levels of lithium have high levels of obesity.

Secondary Inferences

  • S1 – From D2, K1, K5: Exposure to subclinical doses of lithium causes weight gain. 
  • S2 – From D2, D4, K2, K5: Long-term exposure to trace doses of lithium causes weight gain. 
  • S3 – From C1, C2, O2, O3, O5, K3: People are regularly exposed to trace doses of lithium in their drinking water, especially people in areas with notable fossil fuel prospecting like the US and the Middle East.
  • S4 – From C11, O4, K4: People are regularly exposed to subclinical doses of lithium in their food, especially people who eat food grown in areas with notable fossil fuel prospecting like the US.

Tertiary Inferences

  • From S2, S3, C7: The US and Middle East are so unusually obese because they are both arid regions that produce a lot of fossil fuels, leading to relatively high levels of lithium in the local environment.
  • From S1, S4: The US is a net food exporter, this is why the world in general is becoming more obese.

Predictions

No prediction can be entirely decisive, but here are some predictions that are likely to be true if the arguments above are sound, and lithium is a major cause of modern obesity rates:

  • International variation in obesity rates can be predicted by how much fossil fuels the country produces (not counting sources of fossil fuel that are not concomitant with lithium or that are in locations where they won’t expose people to lithium, e.g. offshore) and how much food they import from the US. International variation is also partially genetic, so even if this is a good fit, it won’t explain anywhere near 100% of the variance between nations. We explore this idea a bit in this post.
  • If someone makes a dataset of US counties that includes a “height in watershed” variable, that variable will be more strongly related to obesity rates than a raw altitude variable. If someone can somehow make a “downstream of how much fossil fuel activity” estimate variable, that variable will match even better.  

Remaining Questions

Assuming lithium causes obesity, 

  • How big of a dose is needed to make most people obese? And where is that lithium exposure coming from? Here are three possible (but not exhaustive) scenarios:
    • Trace doses of lithium are sufficient to cause obesity. Lithium is cleared from the brain so slowly (see e.g. this paper, “lithium has an increased affinity to thyroid tissue … [investigations reveal] the lithium elimination from brain tissue to be slow”) that over a long enough timespan, even very small doses accumulate. 
    • Many people become obese on subclinical doses alone, so the subclinical doses of lithium found in food are sufficient to cause obesity. Trace levels in water have a small impact because they provide a more constant dose that keep levels stable, but wouldn’t be able to cause obesity on their own.
    • Subclinical doses of lithium by themselves are not enough to cause obesity. However, some foods contain more lithium than others. Sometimes you get unlucky and eat foods with such a high concentration they give you a bolus containing a small clinical dose, which over time leads to serious accumulation. Eventually lithium in the brain reaches the same levels as you would see on clinical doses. 
  • We know that some plants concentrate lithium in their soil and/or water. Of the crops we grow for food, which concentrate lithium? What’s the rate of concentration — 2x, 10x, 100x? For various levels of lithium in soil and/or water, how much lithium ends up in various parts of the plant? What other factors influence this concentration? Similarly, how much do animals concentrate lithium in their feed into the animal products we eat? 
  • How do we treat obesity caused by lithium exposure? Is it enough for someone to eat a low-lithium diet? Or do you need to take measures to increase the clearance of lithium from your system? What measures can accomplish that? 
  • What percent of the obesity epidemic is caused by lithium exposure? 100%? 20%? Something in between? What else, if anything, is causing such high rates of obesity?
  • In general, what are the best methods to remove lithium from soil and water supplies?

Alternatives

Some of you may still prefer alternative theories. That is ok.

However, we do want to emphasize that alternative theories should be able to explain the following: 

  • The unusual relationship between altitude and obesity rates in the United States. We say “unusual” because while many people want to pin this on something immediately related to altitude (like the idea that lower oxygen levels at high altitudes cause lower weights), this doesn’t actually match the evidence. First of all, the paper that people generally point to in support of this idea, Lippl et al. (2010), is quite bad. Weight loss was minimal, the analysis looks p-hacked (or at least suffers from multiple comparisons issues), and the study isn’t even an experiment, there is no control group. On top of that, since they manipulate altitude rather than manipulating oxygen directly, so this is at best evidence that altitude causes weight loss, not evidence for any particular mechanism. No points for presenting a paper that finds evidence for the premise trying to be explained, rather than trying to explain it. As for other arguments, Scott Alexander looked at the case in 2016 and concluded that the atmosphere probably doesn’t cause obesity. Also, simple elevation theories don’t actually match the evidence. Low-altitude states like Massachusetts and Florida are relatively lean, and West Virginia is relatively obese. In our opinion, the pattern matches “length of watershed” better than altitude itself (Massachusetts is very low-altitude but also in a very short watershed), and “aggregate drinking water exposure to fossil fuels” even better (West Virginia is high-altitude and near the top of its watershed but also the site of lots of fossil fuel activity).
  • Why the Pima were so obese so early on.
  • Why some professions are so much more obese than other professions, and why those particular professions are so unusually lean or obese.
  • Why Toledo, OH is so unusually obese and Bridgeport, CT is so unusually lean. Why Green Bay, WI is more obese than St. Paul, WI. Why Bellingham, WA is only 18.7% obese while Yakima, WA is 35.7% obese. In general, why the most obese cities and communities are so obese and the least obese cities and communities are so comparatively lean

The lithium hypothesis does a pretty good job explaining all of these observations. As far as we know, no other hypotheses of the obesity epidemic can be squared with them. It’s not like they have seed oils in Charleston, WV and not in Charlottesville, VA. It’s not like food is more palatable when placed in front of auto mechanics than when served to other professions. These are rather strong relationships and they need to be explained.

To be completely fair, there are some similar questions that the lithium hypothesis has yet to explain. Here they are:

Finally

And if you want to learn even more, we strongly encourage you to read:

Lithium in American Eggs

1. Introduction

In our previous analysis, we tested the lithium levels of ten American foods. 

All ten foods were found to contain levels of lithium above the limit of detection, but some foods contained a lot more than others — ground beef contained up to 5.8 mg/kg lithium, corn syrup up to 8.1 mg/kg lithium, and goji berries up to 14.8 mg/kg lithium. 

But of the ten foods we looked at, eggs appeared to contain the most, up to 15.8 mg/kg lithium when analyzed with ICP-OES: 

The Results of the Previous Study 

So for our next study, we decided to look at more eggs. 

The first reason to look at more eggs was to confirm the results of our first study, and confirm that these numbers could be replicated.

The second reason to look at more eggs was to start getting a better sense of the diversity of results. Where the first study gave us a small amount of breadth by comparing several foods, the second study would give us a small amount of depth by comparing several eggs. 

The third reason to look at more eggs was that we might be able to find an outlier, a sample of food that contains far more than 15 mg/kg lithium. Eggs containing 15 mg/kg lithium are somewhat of a public health concern; how much more concerning would it be to find eggs that contain 50 mg/kg, or 100 mg/kg. 

(There are reports of such outliers in other foods, in particular from work by Sievers & Cannon in the early 1970s, who reported an “extraordinary” lithium content of 1,120 mg/kg in wolfberries from the Gila River Valley.)

As in the previous study, this project was run with the support of the research nonprofit Whylome, and funded by a generous donation to Whylome from an individual who has asked to remain anonymous. General support for Whylome in this period was provided by the Centre For Effective Altruism and the Survival and Flourishing Fund

Special thanks to all the funders, Sarah C. Jantzi at the Plasma Chemistry Laboratory at the Center for Applied Isotope Studies UGA for analytical support, and to Whylome for providing general support. 

The technical report is here, the raw data are here, and the analysis script is here. Those documents give all the technical details. For a more narrative look, read on. 

2. General Methods

2.1 Eggs

First, we collected a sample of eggs from grocery stores around America.

We started by purchasing several cartons of eggs from grocery stores near Boulder, Colorado. We bought several different brands, and tried to get a fair mix of eggs, both white and brown, conventional and organic. 

However, this was still not enough diversity for our purposes. So in the meantime, we asked friends from around the country to mail us cartons of eggs. 

Fun fact: Eggs don’t actually require refrigeration, Americans are basically the only weirdos who even keep them in the fridge. Especially when it’s mild outside, they keep for many weeks at room temperature. So shipping these eggs was relatively easy — really it’s just about packaging them with lots of padding so they don’t break. Most of the eggs arrived intact and we’re very grateful for the great care in packaging and shipping taken by our egg donors (ha). 

The list of eggs is summarized in greater detail in the technical report.

From most cartons, we took two samples of 4 eggs. This gave us two measurements per carton, which should give us some sense of how much variation there is within an individual carton.

Each sample was homogenized/blended with a stick blender for 1 minute to obtain a smooth, merengue-like texture. The blended mixture was then transferred to drying dishes and dried in a consumer-grade food dehydrating oven.

We also pulled out one brand for more testing, to assess individual egg-to-egg variability. From the carton of Kroger Grade AA, we took two samples of 4 eggs as normal. Then we took three more samples of individual eggs. The single eggs were blended and dried just as the larger 4-egg samples were. 

When all samples were dried, they were crumbled into a powder, weighed, put into polypropylene tubes, and shipped off to the lab for further processing.

2.2 Digestion

Food samples need to be digested before they can be analyzed by ICP-OES. Based on our results from the previous study, we used a “dry ashing” digestion approach, where samples are burned at high temperatures, and the ash is dissolved in nitric acid. 

Incineration causes organic compounds to exit the sample as CO2 gas, but elements like sodium, potassium, magnesium, and lithium are non-volatile and remain behind in the ash.

2.3 Analysis

ICP-OES generates a tiny cloud of high-energy plasma, the “inductively-coupled plasma” of the acronym, and injects a cloud of liquid droplets into that plasma (hence the need for digestion). ICP-OES then examines the light that is emitted by the plasma as the liquid sample hits it.

In addition to lithium, we also analyzed all samples for sodium. Sodium is chemically similar to lithium, and most foods contain quite a lot, which nearly guarantees a good signal in every sample.

This makes sodium a useful point of comparison. At every step, we can compare the lithium results to the sodium results, to see if general patterns of findings match between the two elements.

3. Results

All samples were analyzed as one project, but for clarity of understanding, we’re going to report this project in two parts, as two studies.

In Study One, we look at the main body of results — eggs analyzed as four-egg batches from a single carton.  

In Study Two, we look only at the Kroger Grade AA eggs — analyzed as two four-egg batches and three one-egg batches, to assess individual egg-to-egg variability.

3.1 Study One

 For starters, here is a histogram of the distribution of lithium measurements in our egg samples: 

We’ve previously speculated that the distribution of lithium in food would be lognormal, as it is in drinking water, and indeed this looks very lognormal. 

For comparison, here’s the distribution of sodium:

Note that the x-axis is extremely different between the two plots! This is not surprising; eggs contain a lot more sodium than lithium.

For a sanity check, the USDA says that “Egg, whole, raw, fresh” contains 142 mg sodium per 100 g egg. Converted, that’s 1,420 mg/kg, which approximately matches these results, though the mean in this sample is much lower at only 987.3 mg/kg. The median is 963.0 mg/kg, and the standard deviation is 288.8 all told.

Slightly surprising are those three samples that (according to the analysis) contain almost no sodium — their values in the data are 7.6 mg/kg, 1.5 mg/kg, and one measurement below the limit of quantification. 

3.1.1 By Batch

More interesting is the breakdown by batch.

As a reminder: each carton of eggs (aside from the Trader Joe’s eggs, due to an oversight) was used to create two batches of four eggs each. Then, each batch was tested in triplicate, so each carton was tested six times. Here, each bar indicates a batch. Each batch has three dots, representing each of the three results from the tests done in triplicate: 

The main finding is that lithium was detectable in nearly all eggs. This suggests that ICP-OES is more than sensitive enough for this type of work, and that in general, eggs contain appreciable levels of lithium. 

Most egg samples contained between 0.5 and 5 mg/kg. The few readings of “zero” in the plot actually mean “less than about 0.04 mg/kg moist weight”.

Hypothetically speaking, the batches were all well-mixed. Eggs were blended with a stick blender for a full minute (to a very creamy consistency, think meringue), then dried and crumbled, and the dried bits mixed up. So it’s quite surprising that after all that, there’s so much variance within the batches.

Some of the batches show close agreement between different samples from the same batch. Both Simple Truth AA batches have only a very small amount of variation. Whole Foods Batch 2 is bang on every time. 

But other batches show a lot of variation. Batch 1 of Organic Valley and Batch 1 of Eggland’s best both contain one sample that is a huge outlier. You might dismiss these as some kind of one-off analysis error. But some of these cases, like both CostCo batches or the first Land-O-Lakes batch, show disagreement between all three samples. 

We wondered if this might mean that these batches were imperfectly blended. This would be quite surprising, given the lengths we went to to ensure that the batches were well-mixed. 

If the batches were perfectly blended, then all three samples should contain identical levels of lithium. The only differences between the results would then be errors in the analysis, not real differences in the samples. But if errors were the only source of noise, you would expect to see similar levels of variation in every batch. 

Two explanations seem likely.

First, lithium is very strange. In our last study, we saw that sometimes you get very different numbers for the exact same piece of food. Maybe the differences between different samples from the same batch comes from the fact that it’s hard to get accurate measurements for lithium levels in food.

Second, perhaps eggs are just goopy. It’s possible that despite our best efforts to completely blend the samples, they are still less than perfectly mixed, so some samples from the same batch contain more or less lithium than others. 

We can test these explanations by comparing the lithium results to the sodium results for the same set of batches and samples. If the variance is the result of a problem with lithium detection, then the sodium results should be much more consistent within batches. But if the variation comes from the eggs being imperfectly blended, then we should see similar variation in the sodium results as in the lithium results. 

3.1.2 Sodium

Here are the sodium results: 

Sure enough, there is a lot of variation between sodium levels, even within single batches. This suggests that the variation we saw in the lithium results is not the result of something weird about lithium. It’s probably something general about the samples or the analysis. 

Some of the variation in sodium lines up with the lithium results. The Whole Foods batches show great precision for both lithium and sodium, suggesting that they are especially well-blended or homogenous or something. But there is also some disagreement. For lithium, Organic Valley Batch 2 was much more precise than Organic Valley Batch 1. For sodium, it is the opposite. 

Sodium does show something unique — three very clear outliers with readings of almost exactly zero sodium (specifically 7.6 mg/kg, 1.5 mg/kg, and one reading below the limit of quantification). 

These look like errors of the analysis rather than real measurements. All three are outliers from the sodium data in general, more than three standard deviations below the mean. All three are from different batches and starkly disagree with the other samples from that batch. And we have strong external reasons to expect that any bit of egg will contain more than zero sodium.

In addition, we notice that these three cases with exceptionally low sodium levels are the exact same three cases that registered as below the limit of quantification for lithium. This suggests that none of these readings are real, that there were three samples where something went wrong, and the analysis for some reason registered hugely low levels of sodium and no lithium. If true, that means that all real measurements detected lithium above the limit of quantification.

The other variables we considered, like location, egg color, and whether or not the eggs were organic, didn’t seem to matter. Maybe differences would become apparent with a larger sample size, but they’re not apparent in these data.

3.2 Study Two

You might expect that hens from the same farm, eating the same feed, would all have roughly similar amounts of lithium in their eggs. For the same reason, it seems likely that any two eggs in the same carton wouldn’t be all that different, and would contain similar amounts of lithium.

All the above seems likely, but we actually have no evidence. It’s an assumption, and exactly the kind of assumption that could really confuse us if we assume wrong. It’s worthwhile to check.

Certainly the results from Study One call the assumption into question. A thoroughly blended mix of four eggs seems like it should have homogenous levels of lithium throughout. But empirically, that isn’t what we saw. We saw a lot of variation. Maybe the variation within those 4-egg batches comes from differences between the four eggs.

To test this, we did another round of analysis, focusing on a single carton of Kroger eggs. As before, of the 12 eggs in the dozen we took two groups of four to create two four-egg batches.

In addition, we took three of the remaining four eggs, and used them to create three one-egg batches, mixing and sampling just that single egg. The one-egg batches each consisted of a single egg from this carton, blended well. The one-egg batches were also tested in triplicate, i.e. three samples from the same egg. 

Here are the results: 

These four-egg batches look much like the four-egg batches tested in Study One. They show a lot of variation between the samples tested in triplicate.

The single-egg batches, on the other hand, did indeed have lower variance than the 4-egg batches. There was much closer agreement between different samples from the same eggs, than samples from different eggs. Certainly we see a difference between the egg used for Batch 3, which all samples indicate contains about 1 mg/kg lithium, and the egg used for Batch 4, which all samples indicate contains about 5 mg/kg lithium

This suggests that there really may be appreciable egg-to-egg variation. This could be the result of other factors, including simple randomness, but the tightness of the single-egg analyses is suggestive. And the fact that the variance seems much lower in single-egg batches implies that the mixed four-egg batches are imperfectly blended.

The sodium results for these batches seem to confirm this, with greater variation in sodium in the four-egg batches than in the one-egg batches: 

Again, this suggests that the patterns we observe in the lithium data are the result of actual results in the world, or the analysis in general, rather than some artifact of the lithium analysis in particular.

4. Discussion

Nearly all egg samples contained detectable levels of lithium, and around 60% of samples contained more than 1 mg/kg lithium (fresh weight). These results appear to confirm that eggs generally contain lithium.

If you accept the argument that the three samples with conspicuously low sodium readings are the result of a failure of analysis, then all egg samples contained detectable levels of lithium. 

In terms of diversity of results, samples varied from as much as 15 mg/kg Li+ to as little as less than 1 mg/kg Li+. Variation did not seem to be related to the geographic purchase origin of the eggs. Nor were there any obvious differences between organic and non-organic, or white and brown eggs. This suggests that these are not major sources of variation. 

However, we did see evidence of a lot of variation in lithium levels between individual eggs, even between individual eggs from the same carton. 

While there was a lot of variation between samples, some samples showed a great deal of consistency, especially samples from single eggs. This suggests that dry ashing followed by ICP-OES has high precision when analyzing food samples for lithium. Though these results do not speak to whether or not this analytical method is accurate for such samples, they do suggest that these are real measurements and not merely the result of noise or analytical errors.  

One of our hopes for this study was to find an egg that contained more than 15 mg/kg lithium, that we could subject to other, less sensitive analytical methods. This would let us get a sense of accuracy by triangulation, comparing the results of different methods when analyzing samples of the same egg.

We did in fact find eggs that contain such high concentrations. Above we reported the lithium concentrations in fresh weight, because those are the numbers that are relevant if you are eating eggs. But in terms of analysis thresholds, the numbers that matter are the dry weight. For dry weight, some of these egg samples contain as much as 60 mg/kg lithium. That’s more than enough to be above the sensitivity of a technique like AAS. 

As we are quite interested in trying to confirm the accuracy of lithium analyses in food, one next step will be to replicate these analyses using other analytical techniques like AAS.

The Double-Headed Model of Obesity

A control system is a mechanism — mechanical, biological, or otherwise — that forces a measure towards a reference. One example is a thermostat. You set the desired temperature of your house to 73 degrees Fahrenheit, and the thermostat springs into action, to get its reading to 73 °F or die trying.

The usual assumption is that a control system works like a target, and tries to correct deviations from that target. Take a look at the simplified diagram below. In this case, the control system is set to the target indicated by the big arrow, at about 73 °F. Since control is less than perfect, the temperature isn’t always kept exactly on target, but in general the control system keeps it very close, in the range indicated in blue.

However, there are other ways to design a control system. 

One way is to make a single-headed control system, that has a reference level, and simply keeps the measure either above or below that level. For example, this single-headed control system is designed to keep the temperature above 70 °F:

This is how early thermostats worked, and how many still work in practice. They do nothing at all until the temperature drops below some reference level, at which point they turn on the furnace, driving temperature upwards. Once the temperature returns above the reference level, the furnace is switched off. Barring any serious disturbances, this keeps the temperature in the range indicated in blue. 

This works fine if your house is in Wales or in Scandinavia, where things never get too hot. But what if you want to control the temperature in both directions? 

Easy. You just add a second single-headed control system on top of the first one, controlling the same signal in the opposite direction. This is a double-headed control system, that keeps the signal between two reference values: 

One “head” kicks in if the temperature gets too low, and takes corrective actions like turning on the furnace. The other kicks in if the temperature gets too high, and takes corrective actions like turning on the air conditioning. Together they form a larger control system that, barring any damage or huge disturbances, keeps the temperature in the range indicated in blue.  

(Both “single-headed” and “double-headed” are terms of our own invention. There may be official terms for these concepts in control engineering. If so, we haven’t been able to find them. We would love to hear if there are existing terms, please let us know!)

There is some reason to think that biological control systems in animals are mostly double-headed. This is due to the fact that these control systems are built out of neurons, and neural currents are in units of frequency of firing. Unlike other signals, frequency of firing can’t be negative: the number of impulses that occur in a unit of time must be zero or greater.[1]

Obesity

The current scientific consensus on obesity (link, link, link, link, link) is that it is the result of a problem with the control system(s) in charge of regulating body fat, the set of systems sometimes called the lipostat (lipos = fat). 

We can explore this idea through a few examples. For the purposes of illustration, let’s use BMI for our units. BMI isn’t perfect as a measure — obviously your nervous system doesn’t actually measure its weight by calculating BMI — but it’s a simple and familiar number that will do the trick. In general we should make it clear, all the following examples are greatly simplified. In reality, the body seems to have many control systems to regulate body weight, not just one. 

For starters, we know that the lipostat can’t be single-headed, because with ready access to food, people don’t generally starve to death, nor do they become fatter and fatter until they burst. 

Clearly body weight is controlled in both directions. This means it’s a double-headed system. One part of the lipostat keeps you from getting thinner than a certain threshold. And another, separate part of the lipostat keeps you from getting fatter than a different threshold.

On to the examples. A person with a healthy lipostat would look something like this: 

The two heads are set to different points, leaving a bit of room between the upper and the lower thresholds. This person’s weight can easily wander between BMIs of about 20 and 23, pushed around by normal behavior. But if they go above that upper limit, or below the lower limit, powerful systems kick into play to drive their weight back into the blue range between the two heads of the system.

What about someone whose lipostat is not healthy, someone who has become obese? One way for this to happen is for both heads to be pushed to higher thresholds, like so:

Here you can see that the upper head has been set to a BMI of about 35, and the lower head to a BMI of about 31. As before, their weight is mostly free to wander between those two levels. If they’re trying to lose weight, they can probably push their BMI down to 31. But it will be very hard to push it past that point, since the lipostat will resist them vigorously. After all, the lower limit is designed to keep us from starving to death, so it has a lot of power behind it. 

On the other hand, this person basically doesn’t have to worry about their BMI climbing above 35, since the upper limit is also defended. As long as their lipostat isn’t disrupted any further, they will remain within that range.

However, the heads don’t have to move together. They are at least somewhat independent systems, with separate set points. So another way to become obese is like this: 

This person still has a lower limit of BMI 20, just like the healthy person in the first example. But they have an upper limit of BMI 35, as high as than the obese person in the second example! 

This person is sometimes obese. On the one hand, unlike a person with a healthy lipostat, there’s nothing to keep this person’s weight from drifting up to a BMI as high as 35. So if they’re not “careful”, if they eat freely and without particular attention, sometimes it will.

But on the other hand, there’s nothing keeping this person from driving their BMI as low as 20, by doing nothing but eating less and exercising more. They don’t risk hitting a starvation response until they are well into the healthy BMI range, so they have little difficulty losing weight when they want to.

Lots of people find it really hard to lose weight. But you also encounter a lot of people who say things like, “when I was overweight I just decided to lose some weight, counted calories for a while, and made it happen, and it wasn’t that hard.” The double-headed model may explain the difference. Calorie-counters who sometimes drift upwards but can easily lower their weight on a whim have an altered upper threshold but a healthy lower threshold, while everyone else has had both their upper and lower thresholds pushed to obese new set points, and they face massive biological resistance when they try to return to a lower BMI.

Slightly Complicated

Our friend and colleague ExFatLoss likes to describe obesity as a slightly complicated problem. No one has solved obesity yet, but it doesn’t seem totally chaotic, so maybe there are just a few weird things that we’re missing. We agree that this seems likely, and one way that obesity could be slightly complicated is if different things are causing changes to the thresholds of the upper and lower heads of our lipostats.

To take a traditional example, perhaps eating lots of sugar raises your upper threshold, and eating lots of fat raises your lower threshold. In this model, if you eat lots of sugar but not lots of fat, your weight might drift up, but you can still control it. If you eat lots of fat, your weight is pushed up and can’t be pushed back down.

To take an example that seems more plausible to us, maybe one contaminant raises the upper threshold of your lipostat, and a different contaminant raises the lower threshold. Perhaps phthalates raise your upper threshold. This wouldn’t be very noticeable by itself, because you could still control your weight with diet and exercise. But maybe on top of that, exposure to lithium raises your lower threshold. This would keep you from pushing your weight back down. In combination, exposure to both contaminants would force you into obesity. (We should stress that this is a hypothetical, we have no idea whether these particular contaminants affect one head, or both, or neither.) 

So much for things being slightly complicated. One way that obesity could be very complicated is if there are not just two heads, but lots of them, maybe dozens. This is almost certainly the case. Biology tends to be massively redundant, so the most likely scenario is that the body has several different ways of measuring your body fat, and each of these measures probably has its own control systems. So you probably have many “upper” and “lower” thresholds, all interacting. It might look something like this:   

In this case, there are five heads making for five thresholds. The black thresholds have been forced wide open, defending a healthy lower BMI but a pretty high upper BMI. The red threshold is an additional lower defense, trying to keep BMI above 21. And the white thresholds are fixed to defending a range that’s solidly overweight to obese. This person is most likely to end up somewhere in the range that’s darkest blue, but could see movement all over the place. They won’t face serious resistance unless they try to push their BMI above 35 or below 20. But anything that raised the set point for that red threshold or the bottom black threshold would seriously limit their ability to stay lean.

Again, even this more complicated example is probably an oversimplification. While these models are good for illustration, real biology almost certainly involves more than 5 heads, defending lots of different thresholds in many different ways. 

Your biology defending various thresholds with its many heads.

There is at least one other way in which a person could become obese. As before, you could set the lower limit quite high, say to keep a person’s BMI above 31. Then you could set the upper limit below the lower limit, like so: 

The behavior of such a system is left as an exercise for the reader.


[1]: The systems engineer and control theorist William T. Powers explains this idea in Chapter 5 of his book Behavior: The Control of Perception:

The “reference signal” is a neural current having some magnitude. It is assumed to be generated elsewhere in the nervous system. It is a reference signal not because of anything special about it, but because it enters a “comparator” that also receives the perceptual signal. … 

The comparator is a subtractor. The perceptual signal enters in the inhibitory sense (minus sign), and the reference signal enters in the excitatory sense (positive sign). The resulting “error signal” has a magnitude proportional to the algebraic sum of these two neural currents — which means that when perceptual and reference signals are equal, the error signal will be zero. If both signs are reversed at the inputs of the comparator, the result will be the same. The reader may wish to remind himself here of how a neural-current subtractor works by designing a comparator that will generate one output signal for positive errors, and another for negative errors. (This is necessary because neural currents cannot change sign.)

Philosophical Transactions: JV on Explorations of Isotonic Brine Space

Previous Philosophical Transactions:

JV is a reader and intrepid high-dimensional pioneer who wrote us with some thoughts and comments on the exploration of brinespace. His email is reproduced below, lightly edited for clarity and to help preserve anonymity, but otherwise the same as we received it.


Hello Slimes

I’m a long time reader of your blog and greatly enjoyed your recent post wrt. explorations of brine space. I’ve engaged in somewhat similar experiments due to some health problems (IBS-D is a likely diagnosis but I’m still hoping for something a bit more actionable). Particularly, I had some temporary success about a year ago experimenting with potassium chloride which greatly improved my wellbeing for about two weeks but then, unfortunately, it stopped working. My experiment was similar to Krinn’s in terms of dosage but with the crucial difference that I did not add sugar to the solution. I now understand, thanks to several of your recent blogs and references therein, why this may have caused my experiment to fail.

I’ve decided to give potassium chloride another go, using Krinn’s experiment as a point of departure. In considering the optimal experimental strategy for searching brine space, I conducted a brief mathematical exercise that I think may interest you as well. My brief experiment can be replicated in the attached python script. 

I should probably mention somewhere, that I’m a complete ignoramus wrt. chemistry, so this is a purely mathematical exercise with all the attendant risks of making stupid chemistry 101-level conceptual mistakes.

Anyway, I jumped right in and tried to replicate Krinn’s solution. I don’t have Gatorade easily available, so I used normal lemonade and added roughly two teaspoons of potassium chloride to 1 liter of water along with the normal amount of lemonade (1:4 mixing ratio) and a teaspoon of salt. In short order, I discovered two things: ingesting the solution 1) made me feel better and greatly reduced my appetite (yay!) and 2) made several subsequent visits to the bathroom urgently necessary (boo!). Reading a bit more about the formulation of ORS explained the latter phenomenon: I had inadvertently made a hypertonic solution, meaning that solution drew water into the intestines due to the osmotic gradient. Apparently, this amount of water was such that it could not be reabsorbed. Thus, I arrived at the conclusion that I should make future solutions isotonic (i.e. eliminate the osmotic gradient) or, like the more recent formulation of ORS, slightly hypotonic to facilitate absorption of the mineral salts. 

You may have encountered the formulation of the reduced osmolarity ORS with an slightly hypotonic osmolarity of 245 mOsm/l relative to the previous formation with isotonic osmolarity of 311 mOsm/l (https://www.rehydrate.org/ors/low-osmolarity-ors.htm). It makes sense, to me personally, that the optimal tonicity of any ingested solution should be somewhere in this interval. After all, hypertonic solutions have the major disadvantage that the ingested mineral salts are rapidly excreted, rendering them useless. And so, I assume that any experimental brines should be, at the very least, isotonic but, probably, somewhat hypotonic to facilitate easy absorption. If this assumption is correct, it would have the major advantage, that it significantly reduces the amount of brine space that we need to investigate as the subset of ideally hypotonic brine space (say 245 mOsm/l) is much smaller.

First, I created a script to calculate the osmolarity of Krinn’s solution. In the attached script, the amounts correspond to the ingredients in blue gatorade which result in a calculated osmolarity of 245.6 mOsm/l. I assume it is no coincidence that this closely mirrors the osmolarity of the recent formulation of ORS and, in fact, googling the osmolarity of gatorade, I encountered several criticism of the osmolarity of Gatorade from 10-15 years ago, so I assume the formulation was changed in response.

Of course, this means that adding two heaping teaspoons (slightly less as Krinn was adding them to 20 oz bottles) creates a severely hypertonic solution, which explains my experience with my attempt at Krinn’s solution. This is in no way a criticism of Krinn’s post and, in particular, I note that she writes that she “sips” the solution during the day, which probably explains why she didn’t have any issues. For myself, however, I think it’s better idea to make a hypotonic solution so that I can drink as much as I want.

Second, I created a script to identify the optimally hypotonic subset of brine space in a solution of sugar, salt and potassium chloride. That is, I assume a certain target osmolarity (245 mOsm/l) and amount of sugar (20 g/l) and find the combinations of salt and potassium chloride that results in the optimally hypotonic solution. The result is illustrated below, showing me that I should use quite a bit less of both minerals, close to perhaps 1 teaspoon of potassium chloride and maybe 1/5 teaspoon of salt per liter.

Third, I created a script to do the same for three minerals, using calcium chloride as an example but you could use any mineral salt, really.

Based on these experiments, I conclude that the assumption of the optimally hypotonic solution leads to a subset of brine space that is a linear plane, which should drastically limit the combinations to investigate.

Anyway, I hope you find this interesting and/or useful. At any rate, this is the approach I will take to exploring brine space. If I make any further progress, I’ll let you know.

If you wish, you may freely use or reference this material and the attached script.

Best wishes,

JV

Philosophical Transactions: Leo on Swamp Taters

Previous Philosophical Transactions:

From deep within the metabolic mire, “Leo” sent us a transmission on a potato riff: SWAMP TATERS. Potatoes as high fat, high carbs, low protein. The exchange is reproduced below, lightly edited for clarity.


First Exchange

Leo:

Hey y’all:

A friend of mine and I have been doing an unsanctioned potato-riff (didn’t get around to signing up, didn’t get a good initial weigh-in). Also I can’t remember what day we started but it was probably around January 8. 

I’m down 10+ pounds (from somewhere around 240 to 227; used different scales before I started going to a nearby pharmacy every day or so to use the big ‘health station’) and he’s down probably 20 to 375 (he doesn’t have a scale big enough, is also going to the pharmacy), but was 390+. 

The riff is potatoes + saturated fat (mostly butter, some coconut oil), with calories from the fat no more than maybe 40%. We’ve been strict even about cheat days — only having protein refeeds using bone broth powder for the BCAA restriction as in Brad Marshall’s emergence diet, with a tiny bit of cheese. (The refeed meal is potatoes au gratin boulangeres, with broth in the potatoes and pepper-jack on top). So far a success — we’re both visibly thinner and feeling good. 

A couple of notes:

  • I seem to lose -more- weight after refeed meals. If this keeps up, I’ll experiment with adding bone broth every day. 
  • I ate a bag of potato chips one day, and then fried up a bunch of potato chips in coconut oil the next day, then went up 4 pounds next weigh-in. Possibly just noise, but have religiously avoided both since.
  • He hasn’t eliminated alcohol during this trial, and is still making progress. 

Oh and to make it explicit — we’ll be continuing with the potatoes until we reach our goal weights, and our data for the second month will be better than the first.

SMTM:

So good to hear from you! This is wonderful news.

We’re very interested in this observation about refeeds. We’ve wondered for a while if there might be some kind of second fuel that is the limiting factor, to whatever is causing the weight loss from potatoes. If there were, that would maybe explain why half-tato sometimes works, but often doesn’t, and why some people have so much more success with the potato diet than others.

We like the idea of adding bone broth every day for a week, but then maybe consider following up with a week off, followed by a week adding it back in or something, like an ABA model. If that shows support for bone broth making a difference, maybe folks can riff from there.

We can also imagine that bone broth might have an impact once per week but not the same if done daily. In this case, alternating weeks would also be helpful — you’d see a big weight drop on the first few days of a bone broth week and then less effect after that. 

Leo:

Good thoughts. let’s see:

  • On the refeeds:
    1. The motivation behind adding the bone broth was diet adherence: I’m a lifelong lifter, and my (very large) co-experimenter is a now-crippled former athlete, so we both have a history eating a TON of protein. I implemented the refeed protocol in response to him reporting a tendency to cave late at night and eat cheese sometimes, which matched a certain interior discomfort I had been experiencing. Quite possibly just psychological, but we’ve been maintaining adherence better/easier since implementing them.
    2. My understanding of Brad Marshall’s bone broth (in his emergence diet) is to get enough protein without any of the obesogenic BCAAs. I helped a friend out yesterday in the kitchen but the timing was off — by the time my potatoes were done everyone else was eating burritos, and I ended up eating several spoonfuls of cooked hamburger. Weight went up a pound or so this morning and I don’t believe that’s an accident. 
  • You’re right about A:B testing. I’ll buy some cream today (I tend not to keep it on hand because it’s too easy to overserve yourself adding it to beverages) and try making the au gratin for a week with no broth and no cheese (the cheese was a confounder, anyway). A recipe I’ve invented for the purposes of this diet is a low-protein au gratin dauphinoise that involves making the ‘crust’ on the top (gratin means crust) out of potato flakes mixed with cream. It works as well for the crustiness without the casein. What I expect is that this will have no effect on weight loss in either direction, assuming we control for cheating.
  • Comments on palatability:
    1. Fries defeat the satiating nature of potatoes. Maybe the hot oil and the thin cut allows the heat to more easily destroy the protease inhibitors in potatoes, but i’d have to see the interior temp of potatoes cooked different ways accurately compared to even fully guess this is the case. What I do notice is that even oven-‘fried’ potatoes, if I do them just right, become a food I can eat a ton of without noticing whether or not I’m still actually hungry.
    2. The cheeseless au gratin + colcannon appear the best currently-demonstrated goldilocks option for palatability vs calories. If bone broth clears further trials I’d say that collagen-broth potato chowder and au gratin boulangeres (broth instead of cream) would be the best. Colcannon (mashed potatoes with minimal vegetables in it, traditionally cabbage) requires a lot of butter or cream for appropriate texture.

SMTM:

Great, the ABA designs should tell us a lot! Testing the bone broth is a good starting point. You might also at some point test some of the hypotheses about causes. For example, your results so far are consistent with the BCAA restriction hypothesis, but not very specific evidence for it.

That hypothesis suggests that you should be able to add anything that doesn’t contain BCAAs to this diet without any negative effect, so you could try adding in non-BCAA foods one at a time or something. You could also do an ABA design where you add BCAA powder to your meals directly, to (hopefully) avoid confounders. Hamburger contains BCAAs but it contains a lot of other things too (including lithium, as far as we can tell), it’s suggestive but not a clean test of the hypothesis. 

The most interesting test from a scientific standpoint will be the one where we think there’s a chance one of the conditions might stop the weight loss — see our post about biting the bullet if you haven’t already. From a practical standpoint it’s annoying to interrupt your weight loss, but will be the best sign that we’re getting close to finding the “switch” (or one of the switches at least).

Looking forward to hearing how it goes! 🙂 

Leo:

Ah, yes! I hadn’t read your N=1 series but I agree entirely. 

I’d from the beginning been planning on running this in an ABBB[…]BBBA form, in the sense that I started out making food that was at least 50% potato by calorie, with the rest being saturated fat and cabbage/onions/garlic (sometimes in the form of sauerkraut that I make), with the intention of increasing the tater until I started losing weight. That’s the B. When I reach my goal weight (which barring some miracle will be far sooner than my friend will, given he’s got 150 pounds and negative-6 inches on me, though he’s built like a bull) I’d just add back beef to my own portions (but not his) until I stopped losing weight. 

I’d been thinking of beef as the most obvious source of isoleucine, but you make a good point about the lithium. I have in the past bought bulk BCAA powder and empty capsules and filled them myself (eight years ago on a stint of strictly lifting in the morning despite intermittent fasting on a 20:4 pattern — in retrospect the whole thing was laughable but that’s what I get for not biting the bullet), so I might just buy a big bottle of BCAA tablets and see if I can stop the weight loss with them instead of beef. 

I can already say that adding cabbage (cooked or fermented) appears to have no effects on weight loss, nor does eating massive amounts of capsaicin.

Another thing: I’m experiencing something approaching normal satiety for perhaps the first time in my life. I’ve been doing intermittent fasting for a long time just because once I start eating I don’t stop, and once I eat I crash. So usually I go all day on decaf coffee with butter in it, then eat 4500 kcal of e.g. greasy beef tacos on corn tortillas fried in butter, then become dead to the world. I was never able to lift, barely able to hike after eating. 

That’s all changed. I can eat a bunch of potatoes and lift, or even wait a couple of hours and do sprints or burpees. My IBS is much better, my testosterone levels seem more consistent over the whole day (judging by steady libido and no maudlin period in the evening), and have been sleeping through the night better (less ‘maintenance’ insomnia). I’m a convert already — potato is life.

Second Exchange

Leo: 

Brethren:

Apologies for the long delay, and for this not being as robust a run as I’d intended. I’ve had a lot going on. Only got 3.5 weeks of good weigh-ins. Started a week earlier at probably 240-2, but not on a good scale.

First, the dates with the (good scale) weights:

1/25 – 238
1/26 – 238
1/27 – 236
1/28 – 232
1/29 – 233
1/30 – 233
1/31 – 231
2/1 – 233
2/2 – 231
2/3 – 227
2/4 – 227
2/5 – 226
2/6 – 227
2/7 – 225
2/8 – 225
2/9 – 224
2/10 – 225
2/11- 224
2/12- 223
2/13 – 223
2/14 – 224
2/15 – 224
2/16 – 224
2/17 – 221

We’ve added a graph for the visual learners :‎

My ‘riff’ was adding saturated fat. I wanted to test the metabolic ‘swamp’: high fat, high carbs, low protein. Other potato riffs had reported some dairy, some french fries, etc., but I wanted to control and report the fat intake. 

Protocol was ~7+ pounds of potatoes and at least one stick of butter (often 1.5). After initial weight loss demonstrated that this was working, I wanted to see if additional non-BCAA aminos (i.e. bone broth) would halt it. It didn’t, and I intended to flip that and add just BCAAs, but it’s a good thing I didn’t — I hit a plateau that lasted a week, and would surely have attributed the stoppage to the BCAAs if I’d been taking any. 

17 pounds down in four weeks is a good proof-of-concept of swamping, though. Note that I’m a big guy, and fairly metabolically healthy (I’m barely overweight at 221 and have a fair bit of lean body mass). I was doing this with a friend who was eating roughly equivalent food (slightly less fat) but not weighing in daily. He estimates he lost 15-20 pounds, but he has more LBM than I do. I’d love to see a chart of potato-diet weight loss by LBM rather than by total weight. 

Other consistent elements of the diet were the use of seasonings including MSG and KCl, copious hot sauce, and homemade sauerkraut. Both of us engaged in some kind of intermittent fasting daily as well — my fat intake daily was higher due to blending butter in my coffee in the morning, he just wasn’t eating before noon.

Other notes: a couple of women who ate the same swamp-tater diet a few days reported a reduction in weight of a few pounds, but this isn’t much of a sample. 

Towards the end of the plateau, I was wondering if my metabolism was slowing down (I felt tired and cold more often — this may have been illusory). A couple of days I experimented with stimulating FGF21 in the mornings by eating ~500 calories of table sugar in the am (and no butter). I felt amped while fasting all afternoon, but then ate just as much for supper as I would have eaten between dinner and supper. Probably gained a couple pounds but wasn’t weighing those days. 

I’ll start being more strict with the swamp tater protocol again soon. Overtrained a bit the last few days and hurt all over. Just trying not to psych myself into eating protein as recovery fuel. I should mix up some collagen right now.

Oh, here are my three most successful ‘swamp tater’ recipes. 

Colcannon: (peeled) red potatoes boiled barely enough, then whipped with butter or cream (roughly half stick per five pound bag). while potatoes are boiling, sautee a small head of cabbage, two or three onions, five cloves of garlic pressed (or granulated), and maybe a sliced jalapeno or two. (for sliced, use a mandolin, i’ll link below)

Au gratin: mandolined (peeled) russet potatoes, (optional) cream, hot water, and low-protein bullion (and garlic powder). liquid goes up slightly more than halfway in the taters. then a TINY bit of cheese on top, just barely enough to seal in moisture

Sheet-baked wedges: quartered (peeled) gold potatoes. heat them up by pouring boiling water over them in a bowl, stir until separated and warm, then drain. toss them in a wok with the following: heat a third of a stick of butter, whisk in some frank’s red-hot, a little bullion powder, and granulated garlic. toss them until they’re coated, then put onto baking sheets and cook at 400 until crispy. (do not make these smaller than quarters or they will become ‘fries’ and derange your satiety signaling).

Leo:

I’ve had a lot going on since shortly after I emailed you last, and have found it more or less impossible to stay on any diet. I’ve been largely eating potatoes, sometimes eating a little bread, often eating sugar. 

It feels a bit as I have after weight loss in the past, like what could imagine the experience of an embattled person with an outraged lipostat and part-empty WAT cells might be. Hard to say, beyond 1) fructose sure doesn’t work for me, next time I experiment with using sugar to upregulate my metabolism it’ll be pure glucose; 2) haven’t seemed to suffer as a result of not having more protein; 3) I can now cliff-young-shuffle in zone two (i.e. not even noticing my breathing) as long as I’m not going uphill. This hasn’t been the case for a while, might just be that I’ve been doing a lot of cardio and am 20 pounds lighter; 4) potatoes still taste fine. 

I’m interested in helping map brinespace and will be acquiring a big bucket of confectioner’s glucose as well as bulk supplement bags of magnesium and potassium (maybe in citrate form — KCl makes my teeth hurt). 

I’ll spare you any further reflections I have, as I’ve become a fanatic on linoleic acid (falling short of the colloquial definition of a fanatic: someone who can’t change his mind and won’t change the subject). 

Thanks again for all your good work.

Second Potato Riffs Report


Eating a diet of nothing but potatoes (or almost nothing but potatoes) causes quick, effortless weight loss for many people. It’s not a matter of white-knuckling through a boring diet — people eat as much (potato) as they want, and at the end of a month of spuds they say things like, “I was quite surprised that I didn’t get tired of potatoes. I still love them, maybe even more so than usual?!” (Actual quote from a participant!) And some people lose a similar amount even when eating only 50% potato.

Why the hell does this happen? Well, there are many theories. To help get a sense of which theories are plausible, try to find some boundary conditions, or just more randomly explore the diet-space, we decided to run a Potato Diet Riff Trial. In this study, people volunteer to try different variations on the potato diet for at least one month and let us know how it goes. For example, they might eat nothing but potatoes and always cook their potatoes in olive oil. Or they might eat nothing but potatoes and leafy greens. Or they might eat nothing but potatoes and always eat their potatoes with ketchup. 

The hope is that this will help us figure out if there are other factors that slow, stop, or perhaps accelerate the rate of weight loss we saw on the full potato diet. This will get us closer to figuring out why potatoes cause weight loss in the first place, and might get us closer to curing obesity. We might also discover a new version of the diet that is easier to stick to or causes even more weight loss, or both. 

In the first two months after launching the riff trial, we heard back from ten riffs. Those results are described in the First Potato Riffs Report. Generally speaking, we learned that Potatoes + Dairy seems to work just fine, at least for some people, and we saw more evidence against the mono-diet and palatability hypotheses. 

Since then, we’ve heard back from seventeen new riffs. (Specifically, these are the riffs we heard back from between January 5th and March 18th, 2024.) We will describe these findings in a minute.

More people have their riffs underway or are planning to start soon, so there are more riff trial results in your future. And signups are still open if you want to get involved. But let’s see what we’ve learned so far. 

First we’ll review the overall results, and talk about our interpretation. Then, at the end we’ve included the actual riff proposals and reports from all seventeen participants in an appendix, if you want to read about them in more detail.

Unless otherwise indicated, weight loss numbers are over a period of about 28 days, comparable to the original Potato Diet Community Trial. 

Potatoes + Dairy

Potatoes + Dairy continues to be the most popular riff. Let’s get right to it.

82546219 ate Potatoes + Milk, specifically “because I wanted to prove whoever said ‘no dairy’ wrong”, and lost 19.8 lbs. 

(As before, all these plots have a span of 24 lbs on the y-axis so they can be compared directly.)

32223622 ate Potatoes + Dairy, always potatoes but “dairy … perhaps not every meal but when the mood strikes me!” Results: “Though I struggled to keep a long stretch without cheat days I do not attribute this to the diet itself, rather my work-life balance went to crap and I hardly had the wherewithal to prepare food. This is not typical and was just unfortunate timing for it to happen during this study. In any case, I am happy with the resulting ~5 lbs lost.” This person’s partner also tried the riff and while she did not feel comfortable recording her data, experienced a somewhat stronger effect (see the many interesting details in appendix).

84290728 ate Potato + Dairy, “mainly butter, soured cream, cream; some yoghurt, milk) + ocassional wine”. However, they felt very ill and had to stop after a couple of weeks, and they were not able to record any data. This is an important reminder that some people can’t stand eating this many potatoes, and naturally the potato diet does not work at all for them, even with dairy.

79886833 ate Potatoes + Yoghurt. The verdict? “I really enjoyed it.” See plot:  

37809513 ate Potatoes + “Butter (lots of it)”. A few interesting details here. This participant had previously tried an all-potato diet and wasn’t able to stick with it, but was able to make it through on this riff, though still found it a bit unpleasant. He mostly ate his potatoes steamed, which is notable. In the end he lost 5.3 lbs. 

Potatoes + Dairy + Others

Some people also tried versions of Potatoes + Dairy plus some other stuff, usually vegetables. 

90594710 said, “I’m planning to do the (understandably popular) potato+dairy diet for the first two weeks, and then add in leafy greens for the following two weeks, crossover study style.” This participant had previous success on the potato diet, and notes that while they did lose weight, there was “clearly lost less weight in this riff trial than in my original trial.”

81281674 ate Potatoes + Carrots + Dairy + some other foods, see the appendix for full detail. But safe to say, it was mostly potatoes. They lost 6 lbs in total.

10455414 was an interesting one: Potatoes + Dairy + “Three Sisters”. This participant explains, “I’d like to do the pure potato+dairy for two weeks to see what happens.  One cheat day per week.  Then add in corn.  If that seems to work, I’ll add in the other two of the three sisters: squash and beans.  I’m a member of the Cherokee Nation and think that ‘New World’ grains and veggies are better for you, and that the European additions like beef, chicken, wheat, etc. have screwed up our digestive systems.” He did lose some weight, but he had to deviate from his plan (“I never added the corn. I had some digestive issues so added broccoli, carrots, green beans, and cauliflower.”) and overall this protocol didn’t seem to cause much weight loss:

Potatoes + Protein(s)

Many people have been interested in getting more protein, or concerned about its absence, so we were happy to see several riffs testing the inclusion of various kinds of protein. 

12582676 ate Potatoes + Chicken + White Wine according to a defined protocol (see appendix). He experienced some swings in overall weight but no consistent weight loss, and had problems with energy. “As much as I tried to like this approach, I felt pretty low energy and this is probably not sustainable for me long-term … I need to have energy during the day, and somehow I didn’t end up feeling like I could sustain the required energy level.”

04194992 ate Potato + Red Meat + Dairy. Unfortunately they had to stop after only two weeks, from running out of willpower. This may not reflect on the riff, as this participant is unusually hungry. “I haven’t felt satiety since puberty, e.g. I always want to eat more (I had normal satiety reaction as a child, but this was suddenly lost). … To be honest, I don’t think I would’ve done better with just potato and dairy, I’m too hungry by nature. The amounts of potato and dairy I could consume if allowed to do so ad libitum, are large.”

37791108 ate Potato + Vegan Protein, “either a protein shake or a protein bar with each potato meal… My preferred protein powder is pea protein.” She reports: “I would consider the potato + plant protein a success. I lost 10 lbs/month on full tato but I suspect that I lost muscle during this as well. On potato riff I lost 6 lbs at day 24 but I did not feel like I lost muscle.” She says she might continue this riff so maybe we will hear from her again in a few months! :‎) 

41470698 ate Potatoes + Eggs, though he says, “in hindsight I believe it’s more fair to say I ate three things: Potatoes, Eggs and Olive Oil.” While there was some movement, he generally maintained his starting weight. 

Esoteric Riffs / Other

Finally, there were a few riffs that are hard to categorize or are on a theme all their own.

In the announcement post for this riff trial, we said:

If the whole food hypothesis is correct, eating these processed foods should make the potato diet much less effective. But if you lose weight on potatoes + gummy worms, that’s evidence against the whole foods hypothesis.

22293376 took us up on this with the Potatoes + Skittles riff. “I intend to follow this for a month and see what happens,” he said at the start. “My reasoning is that I believe adherence will be easier when allowing occasional treats, and because I don’t think that refined sugar has a moral valence.” He was right. In fact, “I was astonished at just how well it went.” The last few cheat days here were simply a poorly-timed vacation, but as you can see it didn’t really matter. Check it out:

32602136 went back to that standard potato diet, “plain potato diet, salt, black pepper, nothing else.” As you can see, there were some breaks, but there was also mostly steady weight loss while on the diet: 

75452454 tried a “Whole Foods” + Chocolate diet. This is not really a potato diet, though she did say about 10% of her diet each day was potatoes. In her report she says, “To be honest that was pretty bad, I couldn’t stick to the diet I’d planned for the life of me and definitely gained some weight. If it’s all good I’m going to try a different tact and see how that goes.”

She then did another riff, under the ID 75462073. This was a complex riff, “potatoes + other vegetables + fruit + limited proteins (soy, eggs, fish) + limited dairy (butter)”. She did lose some weight but overall describes the experience as “middling results!”

98821299 ate a diet of fried potatoes supplemented with other foods (e.g. breadrolls, pasta, rice, gingerbread, mayo, soy skyr, toast, etc.). This was more like a half-tato diet as far as we can tell. On this protocol they gained weight pretty consistently: 

Interpretation

Potatoes + Dairy continues to work for many people. However, it doesn’t work for everyone. Adding other ingredients, even fruits and vegetables, seems like it may be enough to interfere, though this is based on just a few cases. 

So far we don’t see a big winner on adding protein, though vegan protein does seem to do better. The egg riff and the meat riffs didn’t work, at least not for these people. This is pretty interesting given that meat and eggs are probably both high in lithium, though in such a small sample size there are many complicating factors. It would be good to see more protein riffs, especially riffs where someone starts off on the all-potato diet (to show that it works for them) and then adds a protein halfway through. We’d also like to see someone else try lentils, since they are high in protein and there was a big Potatoes + Lentils success in the first round of riffs.  

Potatoes + Skittles has a proof of concept. It works just fine, at least for this one participant. More evidence against “mono” and “palatability” as well as “potatoes are a whole food” explanations. We’d love to see more processed sweets riffs, maybe even a Potatoes + 1 Cup Sugar/Day riff!

We’re not entirely sure what to make of the other riffs.

So far it looks like dairy is compatible with the potato diet, or at least some forms of dairy. Vegan protein and sweets, or at least skittles, may be compatible as well. 

Going forward, we are most interested in the following kinds of riffs.

The first is a riff where you add just one thing to the potato diet, and show that you still lose weight. This shows that the new ingredient can be compatible with the potato diet, and if we get a couple of riffs like that, like we have with dairy, it suggests that the new ingredient is broadly compatible. We’d love to do a random walk towards the efficient frontier of fat loss, and maybe there is some super version of the potato diet that has yet to be discovered. (Perhaps Potatoes + 1 Cup Sugar/Day 👀)

The second is a riff that clearly shows that some ingredient stops the potato diet. To do this convincingly, you need to first show that you lose weight on the potato diet (since some people simply don’t), and that you stop losing weight when you add this new ingredient. The most interesting riffs going forward might start with 1 or 2 weeks of the classic potato diet as baseline, so it’s clear that the original version works for you. Then you can add one or two ingredients and see if they stop the effect. 

However, ruling foods in or out isn’t our main interest. What we really want is to make theoretical progress towards the question, why does the potato diet work (and sometimes not work)? Similarly, we would love to know why the half-tato diet works great for a few people but has a tiny effect on average. Maybe it has to do with what you’re eating in the other half?

We feel that the riffs so far have ruled out explanations like “the potato diet is a mono diet (and those work for some reason)”, “the potato diet is low-palatability, ignore the people who say how delicious it is”, and “on the potato diet you are eating nothing but whole foods.” However, if you disagree and feel that you can make a coherent case for why, we’d love to hear from you. Same if you have other explanations that might be tested by some new riff(s).

Sign Up Now

Signups for the potato riff trial are still open, and will probably stay open for all of 2024. You can read the original blog post here and sign up at the bottom. Feel free to replicate one of the riffs described above, try an extension, or invent your own riff. It’s up to you!

We’ll be back in a couple months when we have a new batch of riff trials big enough to report. For now, enjoy the full riff reports below.‎ ‎:‎) 


82546219 – Potatoes + Milk

Riff 

I plan to eat only potatoes and drink one cup of milk per day. CuoreDiVetro mixed dark chocolate with 250ml of milk in their trial. While it’s highly possible the dark chocolate is the active ingredient, I want to isolate the milk as a variable. Milk also contains Stearic Acid so it will be interesting to see whether it’s enough on its own. Europeans have been drinking milk far longer than they’ve been eating chocolate so I’m also curious about that component. Also by drinking milk I won’t have to supplement as much b12.

Report

Thanks for this! I’ve been following you from the very early days. I watched the original potato diet with much fascination and so it was great fun to be involved in this round. 

Here’s my report as such, it’s more just a rambling account on how I went rather than anything resembling scientific rigour. I’m quite interested in the science of it all but content to be a data point this time around.

I’m a pretty stubborn person. These kinds of extreme diets seem to suit me as I’m largely incapable of moderation or calorie restriction but very good and really firm rules. I’m also the designated waste disposal unit at any dinner table. A feature which is used by every friend group I’m in. I’m always the residual consumer who finishes all the food at the table. Partly because I hate to see anything go to waste, partly because I like it, and partly because that is the role I’ve come to assume in these friendship groups.

I chose potato and milk because I wanted to prove whoever said “no dairy” wrong. It just didn’t make sense to me why dairy would negate any effect the potatoes had. I liked the various theories about stearic acid and given milk is a good source of it thought that would put it to the test. I didn’t know that pretty much all your other participants were going to try something similar. I also very much thought the Riff trials were about isolating a single particular item. So when the first batch of Riff trials were released a few days into my experiment I was shocked to see others had done dairy as an entire category, what I would have done for a little cheese.

In saying that the first few weeks of the potato and milk diet were enjoyable. In a weird way there was a freedom in knowing I couldn’t eat anything else. I actually love both milk and potatoes and eating them exclusively almost wasn’t a challenge. At least not for the first few weeks. Experimenting with different ways of doing potatoes was fun and knowing I could eat as much as I wanted didn’t make it a chore. I’m a reasonably active person and my biggest worry was that this would effect my energy levels or performance in training, fears that were largely misguided. Towards the end I had one day where I felt incredibly faint after exercise but this may be more likely down to dehydration. I definitely had a bit of trouble with dehydration early in the diet, my urine was incredibly dark, I assume that’s from a drop in water content from what I was eating. I just doubled the amount of water I was drinking until I felt I was back to my baseline level of hydration.

I got many incredulous looks when telling people I was only eating potatoes. Most people were excited to see how it would pan out, many however didn’t believe it was “possible”. I deliberately kept it from my immediate family because they would think it was stupid. This was borne out when they did find out at the end of the 4th week and told me as much. Once I got known as the potato guy things also got easier because people stopped pushing me to eat other things or putting me through the Spanish Inquisition.

Probably the hardest part of the diet was prepping enough potatoes to take to work and for after work events. I play trivia several times a week, go to a weekly dinner at a friend’s place, and do a couple of group exercise things at night. Not having anything prepped meant it would be fries or packets of chips for dinner, both I grew quite sick of. In saying that I treated myself to some KFC chips on 3 different occasions. Something I normally reserve for when the State of Origin and NRL Grand Final are on.

The routine I came up with was to roast about 8kg of potatoes on the Sunday evening and box them up to be reheated through the week. I also boiled some potatoes on Sunday and boxed them, they could then be cut into discs and fried (my favourite format) or just eaten whole in a pinch. On top of this I tried hasselbacks, mash, baked, chips, and rosti’s. You’d think I would have eaten a lot of mash given my milk allowance but I actually wanted to drink the milk separately. Partly because it was often the highlight of my day, partly because I wanted to keep the variables as low as possible, and partly because I only actually felt like mash a couple of times. I originally planned to drink exactly 250ml of milk but that proved too difficult to measure when not in my own kitchen. So some days I was having about a litre and some days a small cup. All the milk I drank was full cream, I find skim too watery.

In terms of how many potatoes I ended up eating I wish I’d been able to count each one and weigh them all. I’d say my biggest day I had around 5kg of potatoes and my smallest around 200g. One thing I definitely think happened for me is I actually just ate less calories. As I could no longer provide clean-up service at dinners with other people, particularly my partner, that was a massive drop in consumption. I also have a big sweet tooth and the removal of refined sugars probably could have made me lose weight on its own. I definitely felt full more easily from straight potatoes. I guess I was also in diet mode and therefore was watching my consumption quite closely.

Towards the end of the diet I was quite keen for it to end. Mainly because I was really starting to crave fresh fruit and vegetables. I couldn’t stop thinking about fresh granny smith apples. I was also craving citrus. My partner started joking I had scurvy given how much I was talking about grapefruit, limes, and lemons. I did notice in the last two weeks I started to develop mouth ulcers, something that I don’t normally experience. By the end they were quite bad. I was taking a B multivitamin and as one of my friend’s loved to say the potato is nearly nutritionally complete so I’m not completely sure what the cause of that could have been. I wondered if it was a change in the bacteria in my mouth. I often thought about my gut biome and the starving little guys who feasted on my usually very diverse diet having only potatoes to eat.

Overall I lost 19.8 Pounds or 9kg. The first 10 pounds were easy and I knew I’d plateau for a bit and then I tend to have a few weeks lag before my body realises it’s a new regime and then it starts responding. So I wasn’t surprised when I lost the rest of the weight in that final week. I’m really happy with that and it’s a great start to the year. I should mention that going into this I’d had a huge Christmas. Every year I put on around 5kg over the Christmas holidays. That weight always seems to come off quite rapidly regardless of the approach because it’s just freshly put on and my sort of resting bitch weight seems to be 110kg. I also decided to do the potato diet about two weeks out and basically gave myself a hall pass to eat however poorly I wanted to in the lead-in. My main task was trying to chop through all the chocolate I got for Christmas so it wasn’t in the house come potato time. This meant I rolled up to the start line at 115kg and I lost that 5kg in the first week alone.

It was tempting on day 29 to keep going but I need at least a week to reset. It’s certainly nice to poop properly again. The social component of it was actually the hardest part, going out to dinner or to friend’s places and only being able to eat potatoes is not easy after the novelty wears off. It is however a good diet trick to have up my sleeve given I’m getting married at the end of the year and I’ve still got a bit to lose before I get to a weight I’d be comfortable waiting at the end of the aisle with.

Regards, 

82546219

32223622 – Potatoes + Dairy

Riff 

I will be having dairy with my potatoes. Perhaps not every meal but when the mood strikes me! I am open to suggestions however. I want to do potatoes for 28 days regardless, figure I could collect some data along the way :‎) 

I would like to start as soon as possible so please let me know!

Report

Hello,

I am writing to inform you that I have completed 28 days of the potato diet (and a final weigh-in on day 29). Overall, this diet was a great experience and while I don’t think I will be as strict going forward, I will definitely continue to eat more potatoes than I used to. Though I struggled to keep a long stretch without cheat days I do not attribute this to the diet itself, rather my work-life balance went to crap and I hardly had the wherewithal to prepare food. This is not typical and was just unfortunate timing for it to happen during this study. In any case, I am happy with the resulting ~5 lbs lost.

As for going “potato mode” like previous subjects have described, I do think I experienced it a little bit. Days where I was not hungry at all but had to remind myself to eat were common, especially in the beginning. As much as I love(d) cheese and sour cream, these honestly weren’t that enticing on this diet, so personally the added dairy component of this riff didn’t do much for me. Aside from butter, still love butter! And I am so happy living in Canada where I can get poutine just about anywhere. Feels more like a “meal” than just a large order of fries.

My partner, who decided to tag along for this diet (but absolutely hates data collection and diets so did not want to record anything for this study haha), definitely experienced more of the “potato mode” than I did. Any comfort foods she ate, she says the flavour was enhanced by a thousand. Despite that, she still had trouble finishing these cheat meals. Interestingly, she does not like her favourite chocolates that much anymore, as now the chocolate tastes off, and the fillings are too heavy (O’ Henry’s with reese’s peanut butter). I had the same thought, and I enjoyed these chocolates previously as well! Note that she didn’t know about this “effect” of the diet until she experienced it and I told her about it. She is 5’0″ and started at 156 lbs and ended at 149.

What’s most shocking to me in all this is how my perception of food has changed. I would actively avoid potatoes at most fast food places, instead opting to get, for example a chicken sandwich and nuggets. Because “common sense” was that potatoes have too many carbs and carbs = bad and protein = good.

84290728 – Potato + Dairy

Riff 

30 days, potato + diary (any – but mainly butter, soured cream, cream; some yoghurt, milk)+ocassional wine. 

Thinking: satiety effect due to proteinase inhibitors, v high in potatoes. I have previously noticed high satiety when eating significant amounts of whole wheat (also high in proteinase inhibitors) + soured cream. Expect normal protein levels to moderate the effect – hence low protein. High fat diary is in there to make the carbs palatable. Wine to maintain social life whilst doing it. 

Would like to run 30 days, whole wheat + diary and  30 days oats + diary, on same principle. 

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Just an update – I am afraid after trying various things over the past two weeks or so I have given up on eating potato + diary 😔.

Reason is feeling ill on it – eating anywhere over half kg potato per day would make me nauseous, extremely thirsty, mildly dizzy, within 2/3 hrs of eating. My digestion also went from perfect to diarrhea every couple of days and cramps. Looks like potatoes do not agree with me if eaten every day in substantial amounts. I don’t have any explanations for this – maybe my ancestors did not evolve to eat potato? 

I have tried having salty water & eating pickles as I thought electrolite imbalance may be the problem – this resulted in a slight improvement, but not substantial enough to make  it manageable. Peeling the potatoes did not help much either.

Have not put anything on spreadsheet as I basically ‘cheated’ every day due to potato ‘side effects’. On average I ate about 400-500g potato / day with some days of no potato due to feeling unwell. More than one meal of potato per day was not manageable for me.  When not eating potato, I have reverted to eating wholewheat. I have lost 2.6kg over 2 weeks, mostly within the first few days presumably water weight? My appetite was relatively low throughout, eating around 1600-1700kcal on average. 

What’s next? Probably doing this with wholewheat + diary instead of potato, as I know I can tolerate it?

79886833 – Potatoes + Yoghurt 

Riff

Potatos + cream/yoghurt / I think that’s a marvelous combination and I know I may not have enough of it thus it will help me to keep it up to the very end of the experiment.

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Hi!

I have finished my four weeks. My riff was only yoghurt eventually. I really enjoyed it. My sheet is ready for you.

I hope it will help you!

37809513 – Potatoes + Butter (lots of it)

Riff 

I’ll be doing potatoes + butter, for 4 weeks.

I’ve tried a potato diet before, and lasted about a week as I found pure potatoes too unpalatable, and too much work to peel all that everyday.

My rationale is that I’m pretty sold on the low PUFA + low BCAA idea, even though I didn’t lose weight on a rice-based high-carb low-fat low-protein supplemented with bone broth diet and all kind of pills before.

I wanted to do another trial, without supplement this time, just in case one of them sabotaged my weight loss, but I don’t feel comfortable doing that on mostly nutrient-devoid white rice. I also wanted to try high fat instead of low fat, as I experienced some increased inflammation during the low-fat diet, which I blame on the PUFA released from my body fat (the symptoms I experienced went away when I went PUFA-free, and made a come back on a low-fat diet).

Also, potatoes cooked in butter are delicious!

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Hi!

Just updating you about my potato riff trial! It went well! I lost 5.3 lbs, which isn’t as much as many others, but I’m still pretty happy with it given that I’ve tried and fail to lose weight with keto, the emergence diet and intermittent fasting this last year, without success.

So what did I do? My riff was potatoes + butter (lots of it).

My typical meal would be steamed potatoes, slathered with butter, seasoned with salt, pepper, and either dijon’s mustard or apple cider vinegar.

I tried other ways to cook potatoes for variety (over roasted, sauteed, …), but in the end the steamed ones were the ones that felt the most satisfying. I didn’t grow tired of them, and still found this meal delicious at the end of the trial. Mid-trial I started to add 15g of fire in a bottle’s stearic a day, melted in the butter, which I replaced with a couple squares of dark chocolate a day for the few last days. I also had some alcohol throughout the trial, mostly bailey’s and vodka mixers (technically, it’s dairyfat and potatoes, right?).

How did I feel? Honestly, not too great. I was a bit bloated at the beginning, but that faded quickly.  I tried eating baby potatoes with the skin once, which is a mistake I never did again as it gave me horrible bloating all night, and a bad aftertaste that’d come back anytime I thought about them. Mid-trial, I started to have some mild feeling of nausea and distaste for potatoes between meals, which weirdly disappeared completely once I started eating (potatoes…). I went from feeling like I was sick of potatoes while I had an empty stomach to loving them once the first bite was in my mouth. During the last week, I had a headache pretty much every day, and the thought of any protein-rich meal would be extremely appetizing, even things I don’t particularly like (like lentils). So when the 4 weeks were over, I broke the diet immediately.

In conclusion? There is definitely something magic about the potato diet, which isn’t impaired by butter. But based on my symptoms, and cravings on the last week, I think this version was too low in protein for me (after all, the butter is diluting the potatoes’ protein). Maybe in some other nutrients too. I might also be reactive to the solanine or other nightshade compound. I tried a full-potato diet before, and I lasted less than a week. The butter allowed me to do this one for the full 4 weeks.

I’m a bit tired of weird restrictive diets at this point, so I’m back on my usual one, but I’ll probably try other riffs in the future, this time focused on trying to reap the weight loss benefit while still feeling good.

Thanks a lot for organizing this, this was a lot of fun to do, and I love reading about people’s various attempts at solving the puzzle that is metabolic disease!

90594710 – Potato + Dairy, then Potato + Dairy + Greens

Riff 

I’m planning to do the (understandably popular) potato+dairy diet for the first two weeks, and then add in leafy greens for the following two weeks, crossover study style.

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My 4 weeks of data are in! Was, of course, fun as always. … I didn’t do any precise measurement for the leafy greens, but can weigh a sample of spinach and then back-estimate how much of that I ate during a given day with spinach indicated. I also have weight data for the 12 days before I started if that would be of any use. (Interesting note: I dropped more weight in this period, Jan 1st to Jan 13th, than I did during my actual trial, without doing anything special. Just holiday weight going away? Unsure.)  

For context, I did the original potato diet (though I allowed myself dairy during that time) and went from ~165lbs to ~158lbs–in other words, it worked pretty alright for me. (I’m on the taller side, so reminder, lower starting BMI -> lower expected % weight loss.) I’ve mostly fluctuated around the midpoint of that range since then. My starting weight for this riff trial was near the lower end of that, at ~159lbs.

Ok, with that out of the way, my riff was that dairy was once again fair game, but this time, I would also allow green leafy vegetables for the last two weeks. No particular reason for this, beyond that I had started craving them during my original trial–a bit of an odd craving, as I’m usually not as good about getting my greens as I should be, though I do also get that craving sometimes even when I’m not thinking about what I eat. Well, that and that leafy greens are “healthy”, so… something something, should make the diet work better, maybe? Turns out my answer to that is “Ehh, looks inconclusive to me.” I did lose weight overall during both the (potato+dairy) and the (potato+dairy+greens) periods: 1.1lbs and 0.4lbs, respectively. Losing less weight while eating greens doesn’t score a ton of points for that approach. However, those numbers can be a bit misleading, as they’re sensitive to local noise at the endpoints of the time periods. The slope of the trendline was more negative when I did have greens: -.0146 without greens vs -.0538 with them.

So I clearly lost less weight in this riff trial than in my original trial. Why? Well, it wasn’t the greens; even if I had lost 1.1lbs in the second half of my riff trial like I did in the first half, that still only gets me to about a third of what I lost in my original trial. One answer might lie in the types of potato preparation I did. In my original trial, my usual diet was hash browns for breakfast, and baked potatoes with a bit of cheese and/or sour cream for lunch and dinner. During my riff trial, I had way more of what people usually consider unhealthy potatoes: hash browns for breakfast, frozen -> oven-baked fries for lunch, and often milk-and-butter-heavy mashed potatoes for dinner; also, about one bowl (like, cereal bowl sized, not popcorn bowl sized) of potato chips a day. I also had way more dairy than in my original trial, snacking on cheese, putting cheese in my hash browns, putting whole milk in my coffee (which I always drank black during my original trial), and so forth. My deviations from these typical meals in the original diet were also fewer and less drastic; I’d occasionally have fries for dinner, but then be back to 2 meals a day of baked potato, whereas during my riff, the exceptions were more along the lines of “cook some potatoes and spinach in a boatload of heavy cream” and then that would be what I ate for the next couple days. Lastly, my vegetables when I had them were–while I did stick entirely to leafy greens–underwhelming from an “eating healthy veggies” perspective. I went through about a pound of spinach, a little over 4lbs of Brussels sprouts (some steamed, but mostly roasted with oil), and one 12oz bag of romaine lettuce. Not too terribly much healthy greenery for a 2-week span where greenery is one of the 3 types of food I can eat. I don’t think exercise was a factor; the only real exercise I did during either trial was go for the occasional walk, and I strongly suspect I got more walking in during my riff than my first trial.

Anyway, first and foremost, this was delicious and fun (and very easy). If you’re still thinking about doing a riff trial and don’t feel strongly about which one to do, I endorse this one as being enjoyable. (Probably less so than potatoes and chocolate, but hey.) If I were to do it again, the changes I would make are:

– Measure more stuff. In my original trial I tracked about a dozen variables and eventually found it a bit tedious. I overcorrected in my riff trial though, only really tracking my weight and a freeform notes field. I definitely wish I’d done more quantitative measurements, such as precise amounts of dairy and greens.

– Lean harder into the greens as a source of fresh, leafy joy rather than just yet another thing to be fried (I often threw spinach in the pan with my hash browns) or cooked with oil. I think I’d’ve had a more enjoyable time and gotten more interesting data if I’d cut out most of my roasted sprouts and instead gone through like 10 bags of romaine.

– Higher starting weight? Is that a thing I’m allowed to say I’d change? I don’t exactly have full control over it (I’ve never tried to gain weight and don’t know if I could intentionally do so–nor have I really tried to lose it outside of mad potato science) and it feels sort of dishonest to try to juice up your weight–either artificially or by waiting for a natural high point in your fluctuation–before starting a diet, even if you have a maybe-somewhat-valid reason to think it makes scientific sense to do so.

81281674 – Potatoes + Carrots + Dairy + Misc.

Riff 

Nearly all potatoes, carrots, some dairy. Allow ketchup, seasoning, and oil without restriction. However, I work somewhere that provides free lunch, so if they happen not to have potatoes, I’m going to just eat a light vegetarian+chicken lunch of whatever’s available. This time around my primary goal is to lose weight, so I’m going to be conservative and stick mostly to potatoes apart from the convenience of free lunches. After I reach my goal of -15 lbs, I may try adding bread to get more data into the hypothesis that bread halts weight loss from the potato diet.

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Hey, I finally got around to filling in the spreadsheet (I had been tracking in a weight app and personal notes until then) and noticed I’m already four weeks in, so here’s that email.

Things seem to be going well, and I’m going to continue until I get to my goal of 155 lb, then add bread and keep going, as planned.

Eyeballing my data, it looks like I was stagnant Feb 7-12, though I can’t think of a reason for that.

FYI I’ve been subtracting the weight of my poop every morning to reduce variance. Hope that doesn’t mess you up.

Let me know if you have any questions.

10455414 – Potatoes + Dairy + “Three Sisters”

Riff 

I’d like to do the pure potato+dairy for two weeks to see what happens.  One cheat day per week.  Then add in corn.  If that seems to work, I’ll add in the other two of the three sisters: squash and beans.  I’m a member of the Cherokee Nation and think that “New World” grains and veggies are better for you, and that the European additions like beef, chicken, wheat, etc. have screwed up our digestive systems.  

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I was initially planning on doing the potato diet for a few weeks, then adding corn, squash and beans.  This is a Native diet – it uses nothing from the “old world” but only what Native Americans ate before the Europeans arrived.

I never added the corn.  I had some digestive issues so added broccoli, carrots, green beans, and cauliflower.  I had a glass of wine most nights, and a cheat night every Friday.

Here’s what went wrong:  I REALLY like potatoes.  I wolfed down bag after bag of Cape Cod Kettle Cooked chips for two weeks, along with a few visits to Five Guys.  I was in heaven.  But I didn’t lose weight for the first two weeks.  What’s amazing is that I didn’t gain any!

When I cut back on the chips and fries, and substituted more baked potatoes, my weight started dropping.  I also started lifting weights, so my fat loss is probably greater than my weight loss.

The net is that I lost about 5 pounds in five weeks.  

Quitting now.  May go back on it later.

12582676 – Potatoes + Chicken + White Wine

Riff 

My riff (description I sent in the beginning): 

  1. unlimited whole potato, maximum source of calories possible 
  2. measured doses of chicken meat (probably 20-40g of extra protein/day) in addition to potatoes because i worry that potatoes don’t give me enough protein -> muscle loss (i need ~70g pure protein according to online calculators) – might substitute for ~30g of protein from canned sardines when out of chicken (easier) 
  3. 3 bottles of white wine on the weekends (fri sat sun) 
  4. likely to completely fast on Monday because it makes me feel better  

Cooking: 

  • * simply pan-fried with a bit of olive oil, OR baked in oven, OR boiled in a chicken soup (for soup will eat all of it so no minerals/nutrients are wasted) 
  • * when eating out with friends, may eat fries to keep company but nothing else. Also may eat frozen hash browns when in super-hurry at home, but still potatoes. 
  • * regular dried spices (salt, pepper, dried dill weed, cumin, etc.) 
  • * will do my best to take the potato skins off because you told me that lots of skins lead to indigestion, but that’s a lot of work, so sometimes just cut up whole 
  • * no dairy, tomatoes, etc. – just maximum potatoes, supplemented with 20-40g of chicken protein, with measured wine on the weekends.

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just wanted to share some notes on my recently completed riff (12582676):

* I stuck to the rules as described in that doc pretty well, cheated only for two days or so during the holidays, as marked in there.

* There are pretty big day-to-day variations, at first because I weighed at different times, later not entirely sure why, but I diligently weighed multiple times each time and recorded everything as is.

* I can think of a few factors: some days I was too lazy to cook enough potatoes so didn’t get nearly enough calories, a few other days ate too much junk potatoes like frozen tater tots or french fries when eating out, maybe that contributed to ups/downs in the numbers

* Overall, as much as I tried to like this approach, I felt pretty low energy and this is probably not sustainable for me long-term. That’s probably the biggest problem for me, I can deal with routine and cooking, but I need to have energy during the day, and somehow I didn’t end up feeling like I could sustain the required energy level.

Fun experiment and I’m looking forward to more experiments in the future!

04194992 – Potato + Red Meat + Dairy

Riff 

Potato+fatty dairy+red meat. I have chronically lowish ferritin levels so I don’t want to skip meat; I like my coffee with milk/creme, so I won’t skip dairy. Therefore, this seems to be the only potato riff diet available to me.

I’ve kept myself at normal weight my whole life with great effort; I haven’t felt satiety since puberty, e.g. I always want to eat more (I had normal satiety reaction as a child, but this was suddenly lost). When eating moderately so that I keep stable normal weight my homeostasis mechanism figures there’s a famine and downregulates heat production and immune response etc, which is not healthy. A month ago I went through a 6-week “keto-diet” (in quotation marks because I ate so much keto-food that I never really reached ketosis) and slowly lost some weight without going into famine mode. However, keto diet is awfully expensive, especially when cooking for a family of four, and also I was badly craving for starchy foods. Yet the high amount of fat may have allowed me to lose weight without physiologically starving, for the first time in my life. So I’ll try potatoes (cheap) with fat (prevents starvation), maybe this works. 

I’ll try to eat meat regularly but not too much (in case high protein makes people fat*). I’ll use heavy cream in coffee, butter in food, and sometimes maybe eat peaces of pure butter from the fridge, in case I get too hungry. Potatoes either mushed, baked or fried. I’ll supplement iron, B12 (and some other Bs), C and D vitamin, that’s my usual.

Will start on 8th January, I’ll try to stay on the diet for 4 weeks, but there’s a high chance that I’ll stop earlier if it turns out to be unbearable. 

___

* It looks like the human diet science has made an almost full circle, starting with blaming fat intake, then sugar and starch, and now it has reached proteins at last. I’m waiting for the blame to fall on fats again, just to be sure it goes in circles. 

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Dear SMTM,

I’m reporting the results of my diet trial (number 04194992, potato+redmeat+dairy).

I quit my trial after two weeks, sorry. Mainly I just ran out of willpower and also I didn’t see any difference from a garden-variety calorie-counting diet. Which may be expected, as potatoes, red meat plus fatty dairy together are a diverse kind of diet, with all the usual macronutrients nicely present.

General information: I decided to keep meat consumption at around 100g a day, which is quite moderate, I thought. I also restricted dairy to reasonable amounts and ate potatoes by far the most. I started out counting calories every day just to know how much I eat and always stopped eating at around 2000 kcal. For context, online calculators tell me to consume 1800 kcal per day to stay at a constant weight. I wanted to eat much more, of course. So I never ate potatoes ad libitum. Should I eat potatoes ad libitum, I’d get very fat very soon. (I once tried to start the potato-only diet, but couldn’t last more than a week, cravings for other foods got too strong.)

This diet started with a nice clear water loss in 2-4 days, then a plateau, some more weight loss after I further reduced the intake of calories a week in (deliberately but against my will as usual). Then another plateau, an inevitable cheat day at my child’s birthday followed by weight gain, and soon after that I gave in. Started with BMI at 24.6 and ended up at 23.7.

I wasn’t horribly hungry or horribly cold, but I thought about food all the time and wanted to eat much more than I did. Also craved for fresh fruits.  

So I would call this diet not working. That supports the conclusions of previous trials by other people who combined potatoes with red meat. Maybe fatty dairy and any other fat would be okay but the protein in even a small amount of meat ruins everything? To be honest, I don’t think I would’ve done better with just potato and dairy, I’m too hungry by nature. The amounts of potato and dairy I could consume if allowed to do so ad libitum, are large. 🙂

I don’t know if this is any use but it’s still a non-zero amount of information. 🫤

Cheers,

T

37791108 – Potato + Vegan Protein

Riff 

I want to do potato with vegan protein. So either a protein shake or a protein bar with each potato meal. I estimate the breakdown would be 25% calories from protein, 5-10% oil or seasoning for potatoes and 65-70% potato. No restrictions on preparation of potato. My preferred protein powder is is pea protein. I also eat protein bars with peanut and soy and wheat gluten. My plan is to try it for January then re-assess.

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Hello Slime Molds,

I would consider the potato + plant protein a success. I lost 10 lbs/month on full tato but I suspect that I lost muscle during this as well. On potato riff I lost 6 lbs at day 24 but I did not feel like I lost muscle.

I actually screwed up the protocol on day 25 and 26 because I went on a vacation and ate like a pig. This was a really bad month for me to do this experiment. Earlier, I had 3 days where I was trapped at work and had to eat their non-potato catering. I had several social events where I ate things like birthday cake to be a part of the group. However, I did not find myself craving these “forbidden” foods so much as I wanted to participate in the gatherings.

Overall I am very happy and am going to continue the protocol, with breaks for social situations. I think even more than the weight loss, it is a huge quality of life boost to feel satiety. It sucks being hungry all the time. Even if I am not dieting, there is a constant gnawing hunger. 

With bread, pasta, rice, and even salad I can go from completely full to starving in 45-60 min. With potatoes I have a more lasting satiety that can go for 2-4 hours depending on various factors.

I seasoned my potatoes so boringness was not really a factor in my diet. Eating beans or tofu for protein did not really seem to effect my results vs a straight protein bar or shake. Ketchup did not seem to effect my results but I also use a no sugar added ketchup. I used some oils and margarine to cook with but tried to use them sparingly and keep it under 5% of my total daily caloric intake.

Also I found out that I have anemia and have probably had it for years. And that I have had shitty doctors who ignored my bloodwork that whole time. I started IV iron treatments for malabsorption in the middle of the potato riff diet. But the doctor said it would take 21-28 days for new blood cells to grow, so I wouldn’t see the results of the iron treatments yet.

41470698 – Potatoes + Eggs

Riff 

I want to try potato + eggs, both ad libitum. 

Reasoning: I’ve previously had great success with the slow carb diet from the book the “four hour body”. Eggs were a staple breakfast item there. Because I had success I believe potato plus eggs should also work. Furthermore eggs are super tasty and contain a ton of nutrients which seems good.

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Hello SMTM,

I have completed the potato riff trial 4 weeks. You can publish this text anonymously in any way you see fit.

I was planning to make a detailed description of my experience, but I’m unsure how to make coherent thoughts about this experience. So I have just written down some tidbits. Make of them what you will.

This was truly novel and weird. I have never done an experiment like this.

Beforehand I set myself to only eat Potatoes and Eggs. In hindsight I believe it’s more fair to say I ate three things: Potatoes, Eggs and Olive Oil. I’m a huge olive oil enjoyer and that’s also how I like my eggs. Adding to that the oven fried potatoes to that results in a good quantity of olive oil. So I think it would be fair to say I ate a lot of olive oil. I have stayed tot the protocol almost every day of the 4 weeks.

I think I marked 3 cheat days. Probably it’s like 4, as one evening I just wanted something different.

I probably ate more eggs than my bodies was telling me to eat. At certain points during the 4 weeks I didn’t really want to eat eggs, but I also didn’t want to peel & prepare potatoes. Sometimes I then did indeed make potatoes, but sometimes I still ate some eggs instead. I should probably have eaten potatoes instead, but I didn’t have the willpower. 

That was one thing that I was surprised by. The sheer amount of potatoes I had to peel. Finding the time in my schedule to do that was interesting. After a while I just started peeling 3 kilos of potatoes in one sitting. I feel like meal prep is very important for following any of these experiments. 

I started trying to mark different things on the sheet, but the effort of even doing the experiment won in the end.

Recipe discovery: Spanish omelets, It’s basically eggs, potato and olive oil, perfect! Hard to make well though, I had mixed results keeping the kitchen and the floor clean.

Tidbit about eggs: In “4 Hour Body” Tim Ferriss recommends eating eggs without yolks or organic eggs. Not sure if this matters, but perhaps there is some substantial difference between organic and non-organic eggs. I stuck to organic eggs for the whole experiment. For the Netherlands, this article lists the different between our “Scharreleieren”, “Vrije uitloopeieren” and “Biologische eieren”: https://www.bnnvara.nl/kassa/artikelen/scharrel-biologisch-of-vrije-uitloopei-wat-is-nou-het-verschil. I only ate “Biologische eieren”.

Bowel movements were truly weird for the first 4-5 days. I had some weird diarrhea, that’s different from the diarrhea I regularly get with heavily processed food. I usually have it the day after when I ordered a pizza for example. With this experiment it was weird though. After eating the sweet potatoes it seems like they just passed through me with no ‘processing’ by my body. It seems that my body adjusted afterward though, because I had no issues the rest of the time. Even though I also tried sweet potatoes again later, those were completely fine.

I felt fine other than the diarrhea. I find these things hard to compare over time, because my remembering self seems so different from my experiencing self. But it seems that I wasn’t feeling much better or worse during the trial.

As for conclusions, the only one I am drawing from this experience is: When I eat only potatoes and eggs ad libitum, I will generally maintain my current weight.

Which is a little disappointing because I was hoping to lose a little. But also it’s different from the status quo, because before the trial I was eating anything a libitum and was gaining weight. So it’s a change from the mean.

22293376 – Potatoes + Skittles

Riff 

Potatoes (fat and salt allowed) + skittles candies. I intend to follow this for a month and see what happens. My reasoning is that I believe adherence will be easier when allowing occasional treats, and because I don’t think that refined sugar has a moral valence. 

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Hi there,

My riff is now complete. I was astonished at just how well it went, thanks for doing all this work!

32602136 – Standard Potato Diet

Riff

Plain potato diet, salt, black pepper, nothing else. I have already prepared an assload of potatoes for the fridge (russet, salad, baby, baking)

Report

Hi, I have some weeks of data complete, but took a break over Christmas period and taking another break now. I hope it is useful.

UPDATE

Hi, I think I will take a semi-break and cease recording data for now – overall I’ve been really pleased with the results. Added some thoughts below:

I read about Penn Jillette’s potato diet and then found SMTM and thought it sounded too good to be true, so I figured it would be worth a shot to lose some excess weight. My potato riff was to include some pepperoni, salami, chorizo and other cured meats to see if they would help with any anticipated cravings for other food and to break up the monotony of only eating potatoes. This turned out to be unnecessary, to my surprise at no point did I become bored of or frustrated with potatoes. They were delicious to start with and remained satisfying the entire time.

I chose a mix of baking, baby, sweet, and red potatoes, always with the skin left on, mostly boiled or baked. I did not use oil or butter, and usually only salt and pepper as seasonings.

I enjoyed knowing that once I had prepared the next batch of potatoes there was no meal prep left to do and nothing to fuss about. The cost of preparing weekly meals was incredibly cheap. If I wanted a snack, the potatoes were ready, if I wanted a larger meal, I would just take more potatoes. I experienced no cravings for any other type of food the entire time and would’ve been just as content with solely potatoes.

The main downside I experienced throughout the last few weeks was taking the time to prepare all the potatoes – baking especially. It often felt like a chore. Storing the cooked potatoes in suitable containers meant that I only had around 2 days worth ready to eat at any time, and I felt a slight resentment that I had to prepare more when they were running low.

I chose to pause the diet over the Christmas period as it wouldn’t be feasible with family meals and such, though after it had ended my weight had not shot back up which was a pleasant surprise.

I saw an immediate drop in weight that leveled off but has stayed off (around 6 lbs) and seemed to fluctuate at random. My lowest weight was reached on the 19th of January despite not doing anything differently, not noticeably eating less or exercising more, and taking several breaks from the diet. Going forward I think I will incorporate far more potatoes into my daily diet, knowing that I can snack on something filling and pleasant that doesn’t seem to have any negative effect on my weight is great. I think if I had solely stuck to potatoes and had no breaks I would’ve lost maybe double the amount of weight, but even though it isn’t a huge amount I am still really impressed with the whole idea. I’ve recommended it to one of my friends and he has begun his own potato diet after reading the blog, so it is pretty convincing.

75452454 – “Whole Foods” + Chocolate

Riff

I’m gonna stick to whole foods and chocolate. I originally lost a lot of weight years ago eating basically cabbage and brussels sprouts every day but during covid I gained some of that back due to stress. I want to commit to a diet of primarily roasted or raw vegetables. I’ll allow mustard, hot sauce, almost no dairy, and only chocolate when necessary.

I should’ve tracked [potatoes] independently but looking back [they] worked out to about 10% of my diet each day.

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Technically completed back in December but then the holidays happened and I forgot to finish the last days of the diary.

To be honest that was pretty bad, I couldn’t stick to the diet I’d planned for the life of me and definitely gained some weight. If it’s all good I’m going to try a different tact and see how that goes.

75462073 – Potatoes + Other Vegetables + Fruit + Limited Proteins (Soy, Eggs, Fish) + Limited Dairy (Butter)

Riff 

I had done one before focusing on “whole foods and chocolate” but I want to narrow that down. I’m doing potatoes + other vegetables + fruit + limited proteins (soy, eggs, fish) + limited dairy (butter). I’m also going to focus on incorporating exercise since I think that helps not with hitting specific caloric goals but creating a widen margin of error for hitting caloric goals. I also think exercise’s affect on mood helps with making better food choices and sticking to a stricter diet. I’m really angling to recreate previous success I’d had losing weight with a more varied diet than just potatoes and that had involved a lot of cole crops, tofu, and avoiding grains and sweets. I intend to submit results at 4 weeks and then continue if I’m having success.

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Hey besties,

I just wrapped week 4 of my potato riff to some, spoiler alert, middling results!

I’ll probably keep tracking for a week or two longer but we’ll see! I don’t think at any point did I feel like I was in the potato zone. I did make a little progress, I’m 7 lbs down from when I initially filled out the form but that’s still less than the 2/week industry standard and came with a lot of ups and downs.

98821299 – Fried Potatoes

Riff

I want to try a Fried potato riff. I think fries and such are delicious. As I’ve been eating rice and pasta for the last few weeks, it’s time for a change. 

I would also like to know if the amount of PUFA is more important than the amount of BCAA. 

This time last year I had lost about 10kg using a table that calculates real calorie consumption based on intake and weight loss. I’ve since gained it back again, but it was stable for quite a long time. It was only when I doubled my BCAA intake from around 10g to 20g that I became heavier. However, this could also be due to strength training or an increase in my vegan butter consumption. I wasn’t aware of the concept of BCAA restriction at the time and I didn’t have much success with PUFA avoidance before. 

I took part in the potassium experiment back then but didn’t stick with it. This stuff is pretty disgusting and after 1-2 weeks I lost all motivation. 

I hope I can hold out this time! 

  • I want to know i the amount of PUFA or BCAA has a bigger impact on bodyweight. 
  • There will be some Potatoes, but also other low BCAA foods like Rice.  
  • “However, for now it wont limit the amount of PUFA. I will use a reasonabel amount of it to cook my food.  Not drink oil straigt from the jug.” 
  • Calories aren´t counted to keep the data somewhat unbiased. 
  • If there is something, it should work ad lib.  
  • If BCAA´s are such important signal molecules it will be refelctet in the data. 
  • If its neither BCAA or PUFA it shoud also show. 
  • A multivitamin suplement is taken every day. 
  • I´m Vegan, so if i write things like “Butter” or “Cheese” its always a Vegan version of it

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Hey There, i fucked around and found (something, maybe) out!

My goal with this messy riff was to find data on the relationship between BCAA, PUFA and body weight.

I recorded protein, BCAAs, fat, PUFAs, carbohydrates and fiber in addition to food eaten for 30 days. Unfortunately, it only occurred to me in the last few days that carbohydrates might also be important. I have therefore only been able to collect 2 data points from them so far. So I will continue my riff for another 30 days to get meaningful data.

I have started to analyze all the data. I may have damaged your summary. I am sorry.

Let’s start with calculated correlations of the individual macros and body data for my weight.

Protein – 0.009195770085

The amount of protein does not seem to be particularly important in my quantities. The trend line is also almost horizontal.

BCAA – 0.0171401008

The amount of BCAA per kg body weight seems to be a bit more important. In the diagram, however, the trend line is completely horizontal.

Fat – -0.5219424632

More fat made me quite reliably heavier the next day.

PUFA – -0.3515048417

The same goes for PUFA. Interestingly, the less fat and the higher the PUFA content, the less weight gain.

Steps – 0.4659220545

More weight = more energy = more exercise.

Calories – 0.3381898136

I’m not surprised either. I have to get rid of the energy somehow.

In the next step I compared the macros I ate the day before with the change in weight overnight.

As already mentioned, the amount of protein seems to have little or no relevance. Both trend lines are almost horizontal. Fats on the other hand seem to make me heavier. However, data on carbohydrates is missing for the comparison.

So what happens next?

I will also record carbohydrates and keep the amount of fat down. I may increase the amount of protein when I see results. I have put on 4 kg for science and I don’t like that.