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?!” 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 two months since launching the riff trial we’ve heard back from ten riffs. More people have their riffs underway or are planning to start soon, so there are more riff trial results in your future. 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 ten participants, 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

The most common riff to date has been one version or another of Potatoes + Dairy, five out of the ten reports so far. Let’s take a look!

72682326 ate Potatoes + Dairy Fat (butter, heavy cream, sour cream), plus a little chocolate, and lost 11.8 lbs. “This is a new low weight for me,” she adds, “I’d say going back 15 years.”

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

05035476 ate Potatoes + Dairy and lost 12.9 lbs. 

69159819 ate Potatoes + Dairy, mostly as mashed potatoes (prepared as “5 pounds of potatoes with 1-2 sticks of butter, plenty of milk and cream mixed in, and cheese on top”) or potatoes roasted in butter, and had coffee with lots of cream. He lost 9.7 lbs, and described the experience as “truly decadent”. This report is interesting because this participant had the lowest starting BMI (just 26.6) of all the reports so far, and because previous attempts at the full-potato diet didn’t work for him. 

38440610 ate Potatoes + Cheese. “My reasoning is that I thought it would be very funny if cheesy potato would work,” he explained in the signup form, “so I wanted to try.” He ate a wide variety of cheeses (feta, cheddar, parmesan, emmental, maasdamer, etc.) and lost 5.2 lbs. 

67475178 ate Potatoes + Dairy + Milk Chocolate, and lost no weight. Despite this, she reports being amazed that the scale didn’t move, given how much potatoes, butter, cheese, and chocolate she was eating. “I have lost an inch of my waist (maybe less bloated?),” she says, “despite eating copious amounts of milk chocolate daily.”

Obviously this is a small sample size, but so far it looks like Potatoes + Dairy works about as well as the original potato diet, where people lost an average of 10.6 lbs over a similar span of time. So tell your friends, “I need to eat more gratin de pommes à la dauphinoise, I’m trying to lose weight!”

Given this, it’s pretty ironic that our one strict rule in the original potato diet was “no dairy”. Oops!

Sustained Weight Loss

78175908 ate Potatoes + Ketchup + Protein Powder (“derived from milk”) and lost 9 kg (about 19.8 lbs) in the process. He does mention that he doesn’t like potatoes, but says that satiety and energy levels were good overall. 

87411834 ate Potatoes + Lentils in a “stew/soup” with butter, along with a few other minor interventions, like “two Gatorade Zeros each with an additional 1 teaspoon of Potassium Chloride per day” as inspired by Krinn. He lost 17.2 lbs over 29 days.

(PSA: Be careful adding more potassium when doing a potato diet because you are already getting a ton of potassium from the potatoes. At some point you will be getting too much, which is dangerous. How much is too much? It’s hard to tell! Again, be careful.)

In addition, here are two plots he provided of the same data: 

40711007 did a riff that can only be quoted: “Potato + Carrot (for vitamin A) + Fish (for B12 & protein) + Marmite (for B12) + salt (I hear it can be lacking if you just eat potato) + olive oil (…honestly it’s the fat source that I had lying around when I decided to commit to the bit) + various seasonings (it’s how I make soup taste of things) + Apples (I’m only about 90% that I’d be getting enough C from potatoes) + sugar-free fizzy drinks.” Despite this list of modifications, he lost 8.5 lbs, “and that was with four explicit cheat days, as well as at least two days with an unwise amount of deep frying even by the measure of ‘amounts of deep frying’.”

None of these riffs seemed to stop the potato effect. In fact, the first two might have accelerated it. Both of them outperformed the average weight loss in the original Potato Diet Community Trial (though they didn’t outperform the extremes; the greatest amount lost in the original study was 24.0 lbs). 

It’s irresponsible to speculate too much from just two examples, but both of them do include more protein. It’s possible that more protein improves the potato diet. It’s also possible that this is just noise. 

Flopped

13910399 ate Potatoes + Toast with Margarine, the toast being for breakfast and an afternoon snack. He lost only 2.4 lbs. It may be that this riff doesn’t work, but there are complicating factors — he had a cold at one point during the study, took a lot of cheat days, and all the potatoes he had were boiled. 

27482609 ate Potatoes + Beef, mostly grass-fed, and using butter as cooking oil. He lost only 2.0 lbs. 

Both of these participants lost weight, but neither of them lost very much. Again, we should be careful about speculating from just two examples, but this definitely makes us curious whether toast, margarine, or beef blocks the potato effect in general.

If you are interested in trying a potato riff (instructions to sign up are below), we’d be very interested to see riffs of Potato + Bread/Toast, Potato + Margarine, or Potato + Beef. 

Even better would be for someone to try 100% potato for 2-4 weeks, to confirm that they lose weight on the normal potato diet. Then they would add toast, margarine, or beef for another 2-4 weeks and see if they stop losing weight. If they do, they can do another 2-4 weeks of just potato and see if they start losing weight again. This could provide strong evidence that the added food somehow stops the potato diet from causing weight loss as normal. 

Interpretation

We’re interested in potatoes because we want to try to figure out the cause and cure for obesity. But you may be reading this because you’re looking for a way to lose weight. In a practical sense, if you’re trying to lose weight, you might want to start by trying Potatoes + Dairy. It seems to work about as well as the normal potato diet, and it’s probably easier to stick to. If it doesn’t work for you, you can always switch to original potato diet. 

Some people think the potato diet causes weight loss because it is a mono diet, a diet where you eat mostly or entirely one food. We already found this interpretation unlikely, and the riff trials provide even more data against it. Potatoes + Cheese isn’t a mono diet. Neither are Potatoes + Dairy, Potatoes + Lentils, Potatoes + Ketchup + Protein Powder, or Potatoes + Carrots + Fish + … + Sugar-Free Fizzy Drinks. Yet all of these diets caused weight loss, for at least one person who has tried them. If you still think another mono diet would work just as well, then please do a riff of your own and send us the results.

Some people think the potato diet causes weight loss because it is boring. This is often linked to Stephan Guyenet’s perspective that very palatable (read: delicious) foods lead to overeating and weight gain. From this perspective, the potato causes weight loss because it is high-satiety and low-palatability, i.e. filling yet bland. If this were true, adding delicious foods like butter and cheese to potatoes should stop or at least slow their weight-loss powers. Right? Fuckin’ wrong! 

Participant 72682326 ate potatoes, various dairy fats, and sometimes chocolate. She described the experience as “I feel like I’m stuffing myself with delicious carby potatoes”, and lost 11.8 lbs over 28 days. Participant 69159819 ate potatoes and dairy, lost 9.7 lbs, and described the experience as “truly decadent”. Participant 78175908 specifically added ketchup “for enhanced palatability” and still lost 19.8 lbs. Read the rest of the reports below to see similar details. Any kind of blandness/deliciousness/palatability hypothesis predicts the opposite: adding tasty foods to the potato diet should make it much less effective, and anyone who is having a decadent time shouldn’t lose weight. Busted.

Given this evidence, we find it hard to take the mono diet or palatability explanations very seriously. If there’s anyone out there who still defends either of these interpretations, we’d love to hear what you’re thinking.

Sign Up Now

Signups for the potato riff trial are still open! And they will probably stay open all year. If you want to help out, or just try it for yourself, 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, chill out and enjoy the full riff reports below.‎ ‎:) 

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72682326 – Potato + Dairy Fat

Riff

Potato + dairy fat 

Report

Hi there – 

I almost can’t believe that 4 weeks have gone by already but here we are. I started at 216 and today I’m at 204.2… I had 6 substantial deviation days, 2 of which were in the past week (family funerals are rough on diet experiments!)

Before I comment on the last for week, I’ll offer a little history about me. I’ve been obese pretty much my whole adult life. I’m 48F, 5’5”, hourglass-ish (ie low-ish WHR), and with one exception when I was in my early 30s, never was able to get my weight reliably below 250. By early 2022, I was up to 270 and had been in that vicinity for at least a couple of years. Before the pandemic I had gotten down just below 250 but the pandemic showed up and I gained back everything I’d lost and maybe a little more. On Feb 22, 2022 (2/22/22, I’m a fan of palindromes) I decided to get serious and lose weight, no matter what. Over the course of 2022, I lost about 50 pounds using what I refer to as my change-up diet(when I get bored, I change it up, so I cycled through CICO, low fat, high fiber, keto, vegetarian, a very brief carni stint, etc etc.) Early in 2023, I came across r/SaturatedFat and r/StopEatingSeedOils on reddit and then was kind of off to the races on that whole thing.  I was having a hard time losing (and even maintaining) at that point and had some luck maintaining the weight loss on TCD. But I wanted to lose more. It was in April/May 2023 that I came across Exfatloss’s stuff and his ex150 experiment so I did that in May/June 2023, starting at 220 and ending at 206. I then had a ton of work travel and various other life events (aka summer in Wisconsin) that made it difficult to keep losing. I stayed under 210 for the most part until some work and personal stress in September/October when things started trending up again, leading to a bit of a freak out and my plan to do a potato spin off (saw someone comment somewhere on Reddit that potatoes + fat was working for them, so I figured what the heck, because I love potatoes and it’s one of the foods I’ve missed the most while doing a fair amount of low carb eating.) About a week in I told Exfatloss what I was up to and he told me about your potato riff and that’s when I messaged you. 

Sorry that was a lot but I just wanted to kind of lay that all out. Here are my thoughts on the last 4 weeks. 

My starting weight. The scale said 216, yes, but average wise my weight going in to this was more like 214, and it was a recent 214 from a previously lower average weight of 210ish. But I was definitely in a gaining trend that I wanted desperately to reverse. 

My ending weight. This is a new low weight for me, I’d say going back 15 years. Back then the low weight that I hit was a brief victory, I got there via keto and I probably stayed that weight for a couple of weeks, if that, then lost the keto battle and put the weight back on and then some. 

The food I ate: basically, I’d have coffee with heavy cream for breakfast and then potatoes and dairy fat (butter, heavy cream, sour cream) for lunch and dinner. I’d usually target eating about 200-250g of potatoes per meal depending on how hungry I was. I’d add enough fat to make it taste good. I’d also be liberal with salt and other seasonings. I would eat slowly so that if I started to feel full, I’d stop before I felt sick (I had a day where I was in a rush and ate too fast/too much and felt terrible the rest of the day.) If I felt like I needed something sweet, I’d have a square of dark chocolate or a Lindt 70% cacao truffle.  

The weight I lost. As I mentioned above, I previously got down to 206 on ex150 back in May/June. My weight loss efforts always take a couple of times to stick so I’m super excited about this weight loss, it makes me think that I can keep losing. I loved the food on ex150 but that way of eating was pretty difficult to incorporate into my life. I’d say that I love this way of eating about as much and it’s easier to make work for me. Easier to make work -> easier to stick with it. 

Speaking of keto. I mentioned it in my notes on the spreadsheet but there were days that I was in ketosis (my wife has a finely tuned nose for keto breath, for better and for worse.) I was really surprised by this. I know I’m not in major keto because I haven’t dropped all the water weight like I did on ex150. I feel like I’m stuffing myself with delicious carby potatoes, so how is that happening? I have a couple of thoughts on that. 

1) the lion’s share of the potatoes I’m eating are yellow or red potatoes that have been cooked/cooled/reheated, so are the carbs lower than I think because of resistant starch, and/or does resistant starch have some magical quality that we haven’t quite sussed out yet

2) is the high quantity of saturated fat and/or low quantity of protein making it easier to get in to ketosis. 

3) something else I’m not thinking of 

Couple of last thoughts: I’m so excited about these results and my plan is to continue to eat like this for the foreseeable future (holidays might be tricky, crossing that bridge when I get there, one meal at a time). A goal I had for this year was to get to onederland, but it was not happening and I decided not to make myself crazy over the holidays by trying to lose weight. I was just going to ride it out in that average 210-215 weight zone and then attack it again in 2024. Now I’m feeling like I could maybe get to that point yet this year. I’m elated at this prospect. 

That was a lot, hopefully not TMI. Is there anything else you’d like to know?

Thanks for doing this! I’m looking forward to seeing other people’s riffs.

05035476 – Potatoes + Dairy

Riff

potato plus dairy b/c i like those things and I read the ice cream hypothesis…would be very interesting if the combo helped wait loss b/c of all the negative pub on dairy in diets

Report

Hi There!

Finished my potato diet! Very happy with the results, some cheat days at the end that kept my weight a little bit up.  Think I have Stockholm Syndrome now and am keeping up with the taters. Best diet ever.

Hope my data can help.  Kept to potatoes plus dairy, didn’t go hard on the dairy, just supplemented my potato intake.  Tried to keep it low in BCAA, but some seed oil hash browns and fries included in there.

Mood and digestion was all great during the diet.  Only cranky one was my wife having to cook for herself ‎:)

69159819 – Potatoes + Dairy

Riff

My intent is to try potatoes + dairy. This riff is particularly interesting for a few reasons. From a lifestyle perspective, this seems like a relatively accessible way to do the potato diet. I love mashed potatoes (the most delicious way to eat potatoes), most of the toppings I put on baked potatoes are dairy foods, and I don’t see any reason I couldn’t roast potatoes with butter instead of oil. Additionally, the last time I tried the potato diet (as an unregistered personal experiment), I think the olive oil I relied on to roast my potatoes upset my stomach, so I’m interested if this approach eliminates that issue.

Potatoes + dairy is also interesting to me from an ancestral health perspective. My family comes almost exclusively from the British Isles, and I recently read a book (“Highland Folk Ways”) that provided a detailed description of the diet the Highland side of my family would have followed. The historic Highland diet was ridiculously high in both dairy and potatoes! If anyone is able to thrive on just potatoes and dairy, it should be me. If I don’t lose weight/feel good (especially if a future riff without dairy does work for me), that would be particularly valuable information for my personal health.

Beyond those more personal factors, dairy seems pretty controversial in health/fitness/nutrition circles, which makes it interesting. More than I decade ago, when I was first learning about nutrition, I remember reading the strength coach Mark Rippetoe talk about putting scrawny high school boys on the Gallon of Milk a Day (GOMAD) diet, and he proposed that milk was uniquely anabolic. (I seem to recall that the proposed mechanism was Insulin-Like Growth Factor (IGF-1), but further details elude me now.) When you’re trying to put muscles on a high school kid, anabolism is good, but not so much if you’re trying to lose weight. At the same time, dairy is a staple of plenty of non-obese cultures (most of Northern Europe, for example, which is where I am genetically from). Anyway, I’ve noticed that I’m confused about dairy, and that makes it exciting.

I intend to start the day after American Thanksgiving (November 24). Thanksgiving is a big potato holiday in my family, so I’ll have plenty of leftovers to get started with. I will continue up to December 24, the next major date that has food traditions associated with it. I intend to use a mixture of russet, gold, and red potatoes. My major foods will be mashed potatoes (made with lots of milk and butter), potatoes roasted in butter, and baked potatoes with dairy toppings (butter, sour cream, cheese, etc.). I will not restrict incidental dairy in my coffee (I often put a small amount of cream or milk, or have the occasional latte), but I do not intend to eat tons of supplementary dairy (e.g., no ExFatLoss-style whipped cream desserts).

Report

I just took my 4 week weight measurement for the potatoes + dairy riff.

Overall results were surprisingly good – almost 10 pounds of weight loss despite eating massive amounts of both potatoes and dairy. Even assuming that some of the initial weight loss was water, it was impressive. I’ve included some implementation details below to add some context, or in case others want to try to replicate the riff.

Mashed potatoes were the MVP meal – 5 pounds of potatoes with 1-2 sticks of butter, plenty of milk and cream mixed in, and cheese on top, generally lasting 4-5 meals. It was truly decadent. I suspect that I ate that for something like 35-40 total meals, with potatoes roasted in butter making up another 10-15 meals. I generally did coffee with lots of cream (2-4 mugs/day) for breakfast, then had potatoes for lunch and dinner at normal times (roughly 12 and 6, but I made no effort to manipulate the times I ate, I just ate when I was hungry). Rarely (something like 5 meals, each indicated on the sheet) I would eat french fries from a restaurant, mostly for social reasons.

Compared to my previous personal experiment with the potato diet, the dairy makes this so much more accessible for me. First of all, it means fewer overall potatoes, since I was getting quite a bit of satisfaction from the hefty amounts of dairy. While I’m very excited to eat non-potato food (my wife commented last night that I have begun to stare longingly at other people’s food), I’m actually not tired of potatoes. (I actually ate leftover potatoes for lunch, despite technically ending my diet yesterday.) Second, having the dairy also pushed me to prepare almost all of my potatoes from an unprocessed state, rather than trying to justify frozen potatoes, potato chips, and various forms of fried potatoes.

The original potato diet did not seem to work for me. Besides the presence of dairy, the other major confounding factor is the preparation method – in my previous attempt, I mostly ate roasted potatoes (probably 50% peeled, 50% unpeeled, roasted with olive oil). In the dairy riff, a majority of my meals were mashed potatoes, which started with peeling and boiling. During this iteration, I noticed that when I ate roasted potatoes, my weight plateaued or went up the next day (I actually started recording that in my notes part way through). I assumed that was just water retention (maybe I just salt roasted potatoes more heavily?), but it was a very consistent pattern. I’ll also note that this argues against the “boiling potatoes removes the potassium, so boiled potatoes won’t work as well” theory from the original riff intro post!

Let me know if you have any other questions, and thanks for organizing this whole thing! I’m excited to see the results of other riffs.

38440610 – Potatoes + Cheese

Riff

My riff is potatoes and cheese. My reasoning is that I thought it would be very funny if cheesy potato would work, so I wanted to try. My plan is to do the 4 weeks, I have no idea how I will feel afterwards so it’s hard for me to say if I will continue. I know from the past two years, in which I recorded my weight to track weight-loss, that I have a much harder time loosing weight in spring time (or even just holding my weight). If this works now, I will repeat it in the spring to see if it still works then. 

Side note: I just did a quick google search if it’s common to gain weight in spring and a quick search suggest the polar opposite. Might just be because I am lazy and not very social, while others are especially active during spring.

Anyhow there is one caveat for me in this: My goal is to loose weight so if this riff turns out horribly (I feel like a good cut-off point is if I gain 10 lbs total at any point relative to my starting weight) my plan is to abort this riff and transition to the traditional potato (pure-tato?) diet. I plan to document everything so hopefully it will still be useful fore someone. If the pure-tato diet also does not work for me, at least I will have suffered for science T^T

Report

thanks for organizing this riff trial. It was a great experience and a lot of fun.

I think generally potatoes + cheese works. I wasn’t very strict to begin with and when I cheated it reset my progress quite a bit.

After week two I started to get fed up with potatoes and also was pretty stressed in general. I think for me the resulting mental state was the biggest hurdle.

Even though I tended to get satiated more easily on the potato + cheese diet in general, in that time I ate more than ever and still felt hungry.

I’m stopping for now because it will be a pain during the holidays and I’m also planning to move flats in January which would make it increasingly difficult to adhere to the diet.

But I like the idea of continuing N=1 experiments after things settled down a bit.

Yours,
participant 38440610

67475178 – Potatoes + Dairy + Milk Chocolate

Riff

Potatoes + dairy + milk chocolate for at least four weeks. I have chosen dairy as I would enjoy the potatoes more with butter and cheese and I’m curious as to the weight loss effects if any. Chocolate because I’m curious about that as well. 

Report

Hi I have completed the four weeks off my riff! I have lost no weight, but I have lost an inch of my waist ( maybe less bloated?). Despite eating copious amounts of milk chocolate daily. My blood pressure has also gone down a bit from 138/95 to 137/87 I’m not sure if that’s of any significance. 

I was amazed I didn’t put any weight on! I ate a variation of potatoes for every meal with either butter and cheese or both. Followed by some milk chocolate or a yogurt mixed with cream. Usually the potatoes were microwaved in the skin. 

78175908 – Potatoes + Ketchup + Protein Powder

Riff 

+Ketchup +100g protein per day (150g powder, made from milk)

Personal Experience with the Potato Diet Riff (November 1st to 28th)

Introduction

• Diet Overview: Engaged in a modified version of the Potato Diet from November 1st to 28th, adding ketchup and protein powder.
• Purpose: To explore the effectiveness and adaptability of the Potato Diet while maintaining muscle mass and energy levels.

Riff Details

• Ketchup Addition: Included ketchup for enhanced palatability.
• Protein Supplementation: Consumed 150 grams of protein powder daily, providing an additional 100 grams of protein from 563 kcal. This was to prevent muscle loss, given the low protein content in potatoes. 
• 

Results

• Weight Loss: Achieved a significant reduction in weight, from 87 kg to 78 kg over 28 days, with a more rapid loss observed initially.
• Hunger and Convenience: Generally, hunger was not an issue; however, the diet’s convenience was sometimes challenging, particularly during busy periods.
• Potato Preparation: Utilized jarred potatoes (425 grams per jar), rinsed and microwaved for a minute, served with ketchup.
• Energy Levels: Maintained stable energy throughout the diet, contrasting previous diet experiences that involved reduced eating.

Observations

• Non-Palatability as a Factor: Personal dislike for potatoes and the unpleasant taste of the protein powder negatively impacted the diet experience.
• Beverage Consumption: Primarily drank water, with occasional sugar-free pop.

Conclusions

• Efficacy: The diet was effective for weight loss, even with the modifications.
• Muscle Maintenance: The high protein intake likely contributed to preserving muscle mass during the diet. No measurements were made.
• Satiety and Energy: Satiety was generally good, and energy levels remained stable.
• Private factor: For privacy reasons, I’ve omitted a factor that may be important. Please don’t update too strongly on my results.
• Palatability Challenges: The diet’s success might be hindered by the non-enjoyable nature of the foods consumed, suggesting a potential trade-off between effectiveness and enjoyment. 

87411834 – Potatoes + Lentils

Riff

“Potato Stoop” – basically a stew/soup of potatoes, onions, celery, red lentils and butter cooked in an Instant Pot (so I’m retaining the broth and hopefully the potassium). I’ll likely add in some supplementing with potassium chloride later when I receive it from Amazon. I’m hoping to stick with it for several weeks.

Rationale: lentils will add some protein and fiber (maybe a good thing?), and the rest is to help make it tasty and “not just potatoes”. I’ll also add salt, pepper, and various hot sauces to keep it from becoming too same-y and bland.

Report

Hey,

I’ve reached the four week mark and wanted to give an update on how things have been going and why I’ll continue with this for a while longer! It doesn’t feel like it’s been four weeks…

Background

I’m a 47 year old cishet white male with a sedentary lifestyle (IT consultant) living in Canada. Over the last few years I’ve gained “The Covid 19” and then some, so this was a good opportunity to try and lose weight for myself and For Science!

Protocol

First up, some details on what I’ve been eating. My eventual-standard recipe has been:

• Approx. 5 lbs yellow potatoes (i.e., eyeball half a 10 lb bag from the supermarket)
• 3 cups water
• 1 cup dry lentils – more on this shortly
• 1/4 cup butter

I cut the potatoes into pieces with a maximum dimension of around an inch; half go into an instant pot, then the water, then the lentils sprinkled on top, the other half of the potatoes (so now we have a half-submerged raw potato sandwich with dry lentil filling) and the butter on top. This cooks in the Instant Pot at high pressure for 11 minutes, preferably with natural release. I then “finish” things by using a wooden spoon to roughly mash the potatoes and combine in the lentils. Serve with hot sauce of choice. Do it all over again in a couple of days.

Aside Number One: Laziness aka “recipe optimization”

Originally I was also sauteing a finely diced onion and chopped celery first before doing the above steps – this added significantly to the prep time and didn’t add enough value to the experience, so I dropped it. I’ve also tried adding some herbs to the recipe but they didn’t do much for it either. Sometimes simpler truly is better. This recipe’s prep time is about five minutes.

Aside Number Two: Lentil options

At first I was using red lentils – they are a better aesthetic option as they dissolve into the cooking water and have little effect on the colour of the end product, maybe even brightening it a little. When I ran out of those I switched to green lentils – they also taste good but the colour of the result is not as inviting. Opinions will likely differ though, and it’s something I’ve adjusted to.

Aside Number Three: Potassium

I read Krinn’s experiences with Potassium supplements with great interest and decided to include this in my protocol. Starting in the middle of week two, I’ve been drinking two Gatorade Zeros each with an additional 1 teaspoon of Potassium Chloride per day. Sadly, the Costco multipack here in Canada doesn’t include “blue”.

Adherence

There have been two days when I’ve been “off” the diet. The first was an all-day industry conference, so I was eating the delicious catered food at the event. The second was after a very long day, I had an alcoholic beverage and then pigged out on the leftovers from my youngest (bagel, chicken fingers, etc…).

I’m allowing myself a “small” quantity of potato chips as part of the diet, as the meals don’t have any crunch to them and I miss that texture. I also will have things like fresh berries. All that said, I’m staying conscious of what I’m eating and staying away from what I would consider my “typical” diet.

In terms of mealtimes, I’ve sort of fallen into a 16-hour fasting period with an 8-hour feeding window. I typically have my first meal at around 11:30 in the morning, and the food day is over by 7:30PM. My potassium supplementation is generally aligned to these times as well.

This hasn’t been a hardship to adhere to because I’m giving myself some grace from being completely strict. Does that make this “riff-ish”? Perhaps, but I also feel that, outside a medical context, people are typically going to be mostly-good at sticking to a strict eating program. I would say I’m achieving the main goal, that the majority of my calories are coming from my riff. Maybe I’d have a different perspective if I was doing a more fun riff like “potatoes and Snickers bars” ‎:)

Results

I’ve been extremely pleased with how this has gone. This first graph shows progress so far (in kilograms, the native measure of my scales) – on the first day I lost almost 3kg, which I assume is water weight. The three bars are the daily weigh-in (blue), a three-day average (orange) and a seven-day average (gray). The smoothed curves show a pretty consistent weight reduction over time after the first day’s outlier reading.

I find the sawtooth peak/drop pattern intriguing in the raw data, but prefer the smoothed data for looking at overall progress.

I also found it useful / inspirational to pull a seven-day rate of change graph for these readings:

It’s a bit of a mess because the lines all overlap, but you can see from the smoothed curves that I’m typically down between 1 and 1.5 kg (i.e. two to three pounds) compared to the reading from a week before. There hasn’t yet been a sign of a decline in the rate of change.

Next Steps

As the graphs indicate, I plan on continuing this for a couple more weeks – at that point it’ll be the holiday season and I will be fully participating in seasonally appropriate food consumption! After that I will resume the diet; it’s working, I feel good doing it, and I don’t feel like I’m missing out.

Thanks for inspiring me to give this a shot!

40711007 – Misc.

Riff

Potato + Carrot (for vitamin A) + Fish (for B12 & protein) + Marmite (for B12) + salt (I hear it can be lacking if you just eat potato) + olive oil (…honestly it’s the fat source that I had lying around when I decided to commit to the bit) + various seasonings (it’s how I make soup taste of things) + Apples (I’m only about 90% that I’d be getting enough C from potatoes) + sugar-free fizzy drinks (realistically if I try to fully abstain from Treats(TM) I might indulge further than planned on other days).

Report

Hello Slime Mold Time Mold,

This morning was the 28th measurement. As I believe you can see from the data (I suppose I’m assuming you have at least read-access to the spreadsheet that you made and then gave me a copy of), in that time I shed a net total of about 8.5lb from my body mass, and that was with four explicit cheat days, as well as at least two days with an unwise amount of deep frying even by the measure of “amounts of deep frying”.

Among other things this is enough evidence for me that on the order of 2 litres a day of aspartame juice sugar free fizzy drinks is not enough on its own to thwart the potato diet. While I would by no means recommend that anyone, ever, rely on crisps (known as “chips” in America) as a main source of any nutrient, even salt – they were close to a logistical necessity during office days, and even with far more packs a day than I’d normally have used, they weren’t a consistent factor in weight gain days.

Going forwards, obviously I’m not going to be able to stick to the exact riff rigorously over Christmas, however “getting most of the calories from taters” seems to have worked pretty well as a medium to long term stratagem – at least until the trend line stops going down. Of course, I’m most certainly adding onions and swede to the list of explicitly allowed foods (can’t really make soup without onions; can’t make tatties and neeps without the neeps), and probably chicken too as it’s a cheaper protein source compared to even the cheapest tinned fish (certainly if you measure by just grams of protein per unit legal tender). Which is to say, I’ll still be taking data, but “had chicken” is no longer going to get a tick of “majorly broke diet”.

Looking forward to analysis of the data – here’s hoping something more useful was got at this stage, beyond “you can add dietary sources of A and B12 with different macro profiles to the potatoes without totally wrecking the diet” and “in a shock not seen since the Pope was confirmed to be Catholic, excessive consumption of deep fried food is correlated with weight gain”.

Kind regards
Mr Cavern

13910399 – Potatoes + Margarined Toast

Riff

My plan is to follow the potato diet but have toast with margarine for breakfast and afternoon snack. When I tried the potato diet for the first time, I had a lot of bread cravings, so it would be great if I could have it and still lose weight. I’m trying out the margarine to see if consuming seed oils hinders weight loss.

Additionally, I’ll also have mandarins and soy milk in small quantities, which are not part of the main plan, but I had them during my first attempt at the potato diet and still lost weight without any issues.

I will follow the diet for 4 weeks (unless I feel unwell or start gaining weight rapidly), and if I see that it works well, I will continue it for a longer period.

Report

I was very motivated at the start, but at the end I was cheating a lot. Also, I got a cold or something last week and I lost some weight due to that. The days I was sick have a note on the “Observations” row. And maybe relevant, all the potatoes I ate were boiled.

27482609 – Potatoes + Beef

Riff

Potato + Beef. My plan is to make potatoes the majority of my food intake, since my normal diet is very high in meat. It wouldn’t be much of a trial for me if I allowed no potato and unlimited beef. I’m not exactly sure how exactly what the restriction will be; perhaps a pound of steak and then as much potato as I want.

I will be using butter as a cooking oil, writing down how much I use per day, and I may also have beef liver on occasion.

I’d like to get back into my gym routine during the trial, and I’m not very much in the mood to experiment with a low protein diet. I also have a freezer full of grass-fed beef and I’d like to actually eat it.

Report

I’ve put my four weeks in, so I’m done. I’m sorry to say this will not be the most insightful or interesting trial you receive, but here it is. I’ve left my few thoughts and comments in the spreadsheet itself.

General notes from the spreadsheet:

I had intended to record mass of potato and steak, but I ended up messing that up enough that it wasn’t worth recording. As you can see, I was not perfect at measuring myself in the morning, either. Sorry about that.

I generally ended up eating equal parts beef and potato, sometimes large majority potato, very rarely large majority beef.

Common recipes include diced potatoes with beef, mashed potatoes with beef, sliced and fried potatoes with steak.

When we finished the Potato Diet Community Trial, we found ourselves in a pickle. The diet worked — people lost 10.6 lbs on average over only four weeks — and we had basically no idea why. No idea what parts of the protocol were essential, and what parts were optional. 

We had no idea what would make it work better. We had no idea what might make it work worse. And we had no idea of the boundary conditions. We told everyone to avoid dairy, but was that really necessary? Is the potato diet very strict, and you need to stick closely to the original protocol? Or is it very lax? When does it stop working, and why? 

Since then, we have investigated a few of these questions. We tested our main hypothesis about the mechanism (potatoes give you high doses of potassium) and the results provided some support for that hypothesis. We tried a 50% potato AKA half-tato diet based on some case studies, but the results were underwhelming. And we’ve encouraged people to do self-experiments that try to get at the same questions. One example is friend-of-the-blog Krinn, who tried higher doses of potassium and consistently lost weight.

We could keep going like this, running one study at a time. But honestly, that would take forever. The problem is that you can easily come up with 100 different hypotheses for what’s going on. Ok, so you run 100 different studies to test each one. But studies take a long time to run — let’s say 6 months per study. Congratulations, you’ve just locked yourself into 50 years of studying nothing but iterations on the potato diet. There has to be a better way. 

So today we’re introducing a new kind of study we call the riff trial. Let’s see how it works!

Variations on a Meme

In a normal study, everyone follows pretty much the same protocol. In some kinds of studies, like randomized controlled trials, participants are randomly assigned to a small number of very similar protocols.

Instead of making protocols standard, the riff trial makes protocols different. In a riff trial, you start with a base protocol, and every participant follows a different variation. Everyone tests their own riff on the original protocol, and you see what happens. 

To give credit where credit is due, the blogger known as ExFatLoss did something like this first. He ran a study where 10 people signed up to try his ex150 protocol. In practice, however, most people tried minor riffs on the original protocol, like adding an “illegal” carrot salad, and they still generally lost weight. This is a better test of the robustness of his protocol, and it’s a more efficient way to explore the design space. 

Now it’s our turn. Today we are starting a Potato Riffs Trial, and we’re looking for people who want to try their own riff on the potato diet. 

A riff trial takes advantage of the power of parallel search. Some riffs will work better than others (or at least differently), and parallel search helps you find these differences faster, especially if the differences are big.

Or if you prefer, it uses the power of evolution. The original protocol goes out with mutations and we see how they do in the face of natural selection. If you want, you can even run a second riff trial on the most successful riff(s), to explore the space even further. In this way, the riff trial is the atomic gardening of study design.

Some riffs will be more compelling than others. If you do a riff and lose weight on that version of the potato diet, this suggests the potato diet is robust to that difference. If you do a riff and don’t lose weight, that’s tricker, because we know the potato diet doesn’t work for some people — maybe you are just one of those people. 

But even when individual riffs don’t prove much, together they can be suggestive. If ten people try potatoes + bacon and they all gain weight, that’s pretty strong evidence that bacon is the anti-potato. You could also account for this by doing a few weeks of the original potato diet to demonstrate that it works for you under normal conditions, and then starting the riff to see if anything changes.

A riff trial is scientific fun for friends and family. If a husband and wife living in the same house try different potato riffs, and have different results, we know the differences aren’t a result of their environment, since they live in the same house and sleep in the same bed and so on. If adult siblings living in different cities try the same potato riff and have different results, the differences are probably due to differences in their cities, since the siblings are closely related and are doing the same protocol.

This is also a way to put your money where your mouth is, so to speak. We love all y’all people on the internet, but some of you talk a lot and experiment very little. Science needs to be more competitive — not in the sense of arguing (bleh!) but in the sense of people actually doing studies to go after their disagreements rather than just theorizing about them. This is your chance to get your hands dirty.

And as always, this is a chance to PLAY with your ideas, to PLAY WITH SCIENCE, to JOIN the INTERNET HIVE MIND and MESS AROUND WITH YOUR FRIENDS. This can be your way to help welcome the 21st century scientific revolution you so desperately crave.

Tl;dr, we’re looking for people to volunteer to eat almost nothing but potatoes (depending on your riff) for at least four weeks, and to share their results. You can sign up below. For more detail, read on! 

Potato Riffs

As a reminder, here is our version of THE POTATO DIET (more detail can be found in the original post):

• Drink mostly water. You can also have other beverages like tea or coffee. Just don’t take them with cream or sugar and try not to get too many calories from your drinks. 
• Eat potatoes. Start with whole potatoes and cook them yourself when you can, but in a pinch you can eat potato chips or fries if you need to. You can calculate how many potatoes to eat (a potato is about 100 calories, so if you need 2000 kcal/day, eat about 20), but we think it’s better to eat the potatoes ad libitum — make a lot of potatoes and just eat as much as you want.
• Perfect adherence isn’t necessary. If you can’t get potatoes, eat something else rather than go hungry, and pick up the potatoes again when you can. 
• Seasonings are ok. Do what you can to keep yourself from getting bored.
• Oil is ok.
• Take a daily B12 supplement, since potatoes don’t contain any. We like this version but use whatever you like. Take vitamin A if you’re not eating sweet potatoes. A multivitamin would also be fine as long as it contains B12. 

Your mission, should you choose to accept it, is to try the potato diet plus some kind of variation of your choice for at least four weeks. You can try any riff you like, but for inspiration, here is a list of ideas:

• Whole foods
  • Potatoes + Avocado
  • Potatoes + Bananas
  • Potatoes + Cashews
  • Potatoes + Fruits
  • Potatoes + Leafy Greens
• Unwhole/Processed Foods
  • Potatoes + Snickers
  • Potatoes + Hot Dogs
  • Potatoes + Soda
  • Potatoes + 10% Ultra-Processed Foods
• Various Fats
  • Potatoes + Butter
  • Potatoes + Olive Oil
  • Potatoes + Sunflower Oil
• Grains
  • Potatoes + Bread
  • Potatoes + Rice
• Protein
  • Potatoes + Tofu
  • Potatoes + Chickpeas
  • Potatoes + Beans
  • Potatoes + Eggs
  • Potatoes + Ground Beef
  • Potatoes + Chicken
• Food Suspects
  • Potatoes + White Sugar
  • Potatoes + Honey
  • Potatoes + Chocolate
  • Potatoes + Cream
  • Potatoes + All Dairy
  • Potatoes + Ketchup
  • Potatoes + Tomato Sauce
• Preparation
  • Potatoes (baked only)
  • Potatoes (boiled only)
  • Potatoes (roasted only)
  • Potato Soup SOUP ONLY
• For Humor Only
  • Potatoes + Molasses

Before you sign up, let’s highlight some riffs we might be especially interested in:

Mono-Diet

Some people think the potato diet causes weight loss because it is a mono diet, a diet where you eat mostly one food. We think this is wrong! If it were true, 1) any other mono diet would also work, and 2) the half-tato diet wouldn’t work because you eat more than one thing. But the half-tato diet does seem to work, at least for some people. Also there was so much cheating in the original potato diet (by design!) that we’re not sure even most of those would could as a mono diet really:

So one very simple riff you can do is the potato diet plus some other food of your choice. Potatoes and apples. Potatoes and lettuce. Potatoes and carrots. If the mono-diet hypothesis is true, adding these other foods should stop the potato diet from working. If it keeps working, that’s a major problem for the mono-ness hypothesis. 

Deliciousness

Some people think the potato diet causes weight loss because it is bland. We think this is wrong too. First of all, potatoes are delicious. Second of all, this doesn’t make any sense. Why would that happen.

However, one riff you could do is potatoes plus one or two foods you think are especially delicious. This seems like a good deal. You get to eat potatoes and one or more of your favorite foods, as much as you want for a whole month, and you might lose weight for your trouble. If you do lose weight eating potatoes and a favorite food, that’s a major problem for the blandness hypothesis. Also it makes sense.

Potatoes + Whole Foods or Unwhole Foods

Some people think the potato diet causes weight loss because potatoes are whole foods — they are totally unprocessed, unadulterated, torn directly from the bosom of Mother Earth. This might be part of it, though it makes us wonder what it might be about “whole foods” that would make them cause weight loss. 

Anyways, one way to test this would be to try eating potatoes plus some other whole food, like almonds or bananas. If the whole food hypothesis is correct, this should cause as much weight loss as the normal potato diet, maybe more.

Or you could do the opposite, and try eating potatoes plus some highly-processed food, like snickers bars or Big Macs. 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.

Potatoes + Cream

ExFatLoss has lost a lot of weight on a diet that is mostly heavy cream. When he recruited ten other people to try the same thing, most of them lost weight too. If potatoes cause weight loss, and cream causes weight loss, maybe potatoes and cream together will cause even more weight loss? 

Worth trying, at least, especially since in the original Potato Diet Community Trial, we asked people to avoid dairy. Maybe that was the wrong move. You could also do potatoes + light cream or potatoes + milk, to see if milkfat matters. Or just a general potatoes + dairy, where you eat both potatoes and any dairy products ad libitum. 

Potatoes + Various Fats

Some people think that seed oils are the cause of the obesity epidemic, and/or are bad for you in general. From this perspective, the reason the potato diet works is that it cuts all the seed oils out of your diet — you’re too busy eating potatoes. As we’ve previously argued, we don’t find this theory very convincing. But it’s easy enough to test. We wrote:

It would be easy to run a variation of the potato diet where half the participants are randomly assigned to eat their potatoes with butter, and the other half are randomly assigned to eat their potatoes with sunflower oil. (Or substitute these for whatever fats the seed oil theorists think are best and worst.) If the seed oil theory is correct, then the participants eating potatoes + butter should lose weight much faster than the participants eating potatoes + sunflower oil. If the seed oil theory is wrong, there should be basically no difference.

This would be a good subject for riff trials. If they want to, some people can sign up to eat olive oil with all their potatoes, some can sign up to eat butter with all their potatoes, some can sign up to eat canola oil, etc. Then we can see if there are big differences between people who choose different fats. 

If seed oil theorists are really confident in their theory, they should sign up and demonstrate that seed oils kill the potato weight loss effect, and other fats don’t.

Potatoes and Suspected Blockers

The potato diet may work by adding things to your diet, like huge doses of potassium. But it may also work by removing things from your diet. (It might also do both.) This suggests that there may be some foods that “block” the potato weight loss effect. You can test this in a riff by trying the potato diet plus one of these foods, to see if it keeps working or not.

One prime suspect is tomato and tomato products like ketchup. Ketchup came to our attention as a result of some anecdotes from the original Potato Diet Community Trial, stories where people felt that eating ketchup kept them from losing weight. As Jack Peterson noted, tomatoes blocking the effect “would explain why no one ever noticed [the weight loss properties of potatoes] prior to Chris Voigt’s stunt: because potatoes are usually eaten with ketchup”. And we were surprised to see that in the Half-Tato Diet Community Trial, weight loss was correlated with tomato consumption, r(36) = 0.37, p = .021 (also significant when removing the extreme outlier, r(35) = 0.36, p = .031). Plot here:  

So you could try a potato diet with ketchup in particular, or with tomato products in general. If you still lose weight, that would show that tomato isn’t necessarily a blocker. If you don’t lose weight, that’s pretty interesting. You could also try alternating weeks with and without tomatoes, to see if you can make the effect turn on and off at whim. Whee! 

Tomatoes are our top bet, but other possible blockers might be: wheat, bread, grains more generally, maybe meat. Carbs stand out because on the potato diet you are getting a lot of carbs. So even if you do take a cheat day, you probably won’t be cheating with bread, because you probably won’t crave that. Some people think sugar might be a blocker, so you could try potatoes + white sugar (but maybe not together, ew). Eggs or goji berries might also be blockers because they seem to be high in lithium. So one kind of riff would be trying potatoes and one of these foods and seeing how it goes. 

Potatoes + Chocolate

CuoreDiVetro recently published a self-experiment where they followed a very simple form of the potato diet, replacing one meal per day with a meal of just potatoes, supplemented by additional doses of potassium chloride (based off of a potassium:sodium ratio hypothesis that has been floating around). This worked very well for them at first — then they discovered that it appeared to work even better when they included chocolate, like so:

I bought dark baking chocolate (100% cacao) with a high concentration of potassium (just in case it was the potassium). I made my hot cacao by melting ~36g of dark chocolate (containing roughly 750 mg of K) in roughly one cup (250ml) of milk (containing roughly 350 mg of K) and sweetening it to taste. 

According to CuoreDiVetro, they lost weight four times faster when they were eating one hot chocolate per day in addition to their meal of potatoes.

This could be something about chocolate in particular. But it might also be yet another pointer to stearic acid, a waxy fat common in foods like tallow, lard, butterfat, and cocoa butter, which for some reason keeps showing up in weight loss research. If you’ve heard of this fat before, it’s likely from Fire in a Bottle (FIAB), a website/program/theory which argues that a diet high in stearic acid can cause weight loss. This is sometimes called The Croissant Diet (TCD), presumably in the hopes of confusing readers — you do not actually eat nothing but croissants. In fact, you don’t have to eat any croissants at all. But you do ideally eat lots of foods high in stearic acid, sometimes supplementing with additional stearic acid, and some people seem to lose weight when they do this.

There are other reasons to think that stearic acid might be involved. ExFatLoss and co must be getting a lot of stearic acid from the huge quantities of milkfat they’re consuming. And Outlier 17 from our Half-Tato Diet Community Trial, who lost way more weight than anyone else in the trial, often took straight stearic acid as a supplement. 

So you could supplement stearic acid on top of your potatoes and see what that does. Or you could try potato + chocolate, which seems more delicious. But to each their own. 

You could also try CuoreDiVetro’s riff exactly, or riff further off that riff. It appears to be 1) one meal per day as a meal of just potatoes, 2) potatoes are salted with 3.2 g KCl, 3) avoid adding NaCl (normal table salt) to potatoes, 4) at least one hot cacao per day, per the recipe above, and 5) otherwise eat as normal. This is really several riffs away from the main protocol and might not be as illuminating, but would give another similar data point for comparison. 

Preparation

We think the potato diet might cause weight loss because of the super high doses of potassium you get when you eat tons of potatoes. We also hear that boiling potatoes removes a lot of their potassium, because it drains out of the potato and into the boiling water. If this is the case, then eating nothing but boiled potatoes would probably cause much less weight loss than eating nothing but baked or roasted potatoes, which should still have all their potassium. Unless you boiled your potatoes as a soup and then drank all the broth.

Doing a riff where you only ate one kind of preparation, whether those be boiled, baked, fried, steamed, roasted, mashed, or souped potatoes, might illuminate this question. But it might be kind of boring.

Half-Tato Accelerator

Many people lose weight on the half-tato diet, like M, Nicky Case, Outlier 17, and CuoreDiVetro. We say “half-tato”, even though many of these people were getting less than 50% of their food from potatoes. But when we ran a community trial of the half-tato diet, most people barely lost any weight.

What gives? Maybe there’s some extra step required to make half-tato work. If we could figure out that extra step, people could lose weight with much less hassle. So if your riff seems to be working on full-tato, you could switch to half-tato and see if it keeps working just as well. Or you could try various riffs on half-tato and see if any of them serve as the switch. 

Get Confused

They say that the most exciting phrase to hear in science is not “Eureka!” but “That’s funny…” So the best thing that could happen would be if you find something really weird. For example, it would be very weird if people found that taking iron supplements makes the potato diet totally ineffective… unless you take iron supplements AND magnesium supplements, in which case it starts working again (we have no reason to think this would happen, just a wild hypothetical). If that happened and it were robust, it would be very surprising, and trying to puzzle it out would get us closer to an answer.

So if you have some other weird potato diet riff you want to try for some reason — we say, go for it!

Sign Up

Ok researchers, time to sign up.

The only prerequisites for signing up are: 

• You must be 18 or older;
• In generally good health, and specifically with no kidney problems;
• Willing to do some version of the potato diet, as described above, for at least four weeks, and;
• Willing to share your data with us — you can publish it as a philosophical transactions post on our blog if you like, or publish it somewhere else on your own.

As usual, you can sign up to lose weight, lower your blood pressure, get more energy, or see one of the other potential effects. But you can also sign up to help advance the state of medical science. This study will hopefully get us much closer to understanding why the potato diet causes weight loss. It might lead to a practical weight-loss intervention that’s much easier than the 100% potato diet, and it might lead to curing obesity for good.

And beyond that, running a study like this through volunteers on the internet is a small step towards making science faster, smarter, and more democratic. Imagine a future where every time we’re like, “why is no one doing this?”, every time we’re like, “dietary scientists, what the hell?”, we get together and WE do it, and we get an answer. And if we get a half-answer, we iterate on the design and get closer and closer every time. That seems like a future worth dreaming of. If you sign up, you get us closer to that future.

Eating this much potato may sound a little daunting, but people who have tried it say that it is much easier than they expected, and delicious to boot. Here’s our suggestion: If you are at all interested in trying a potato diet riff, go ahead and sign up and start collecting your data. Collect your baseline measurements for two weeks, then try the first day or two of the potato diet and see how it feels. If you hate it and have to stop, we would still love to have that data.

If at any point you get sick or begin having side-effects, stop the diet immediately. We can still use your data up to that point, and we don’t want anything to happen to you.

We are mostly interested in weight loss effects for people who are overweight (BMI 25+) or obese (BMI 30+), but if you are “normal weight” (BMI 20-25) you can also sign up. 

And for everyone, please consult with your doctor before trying this or any other weight loss regimen. 

We realize that anyone who starts a potato riff soon will overlap with Thanksgiving and/or Christmas. So you’re welcome to wait and sign up later, we will keep signups open at least through January, maybe longer. But also, it’s not a problem if you overlap with the holidays, and it might be a good way to see how robust your riff is. Someone doing an “I ate potatoes and whatever holiday treats I wanted” would honestly be an amazing study.

In general, signups will be open for a while, and it’s all rolling signups. Pick out a riff and join whenever.

If you were part of previous SMTM studies, please feel free to sign up for this study as well! Just mention it, and provide any previous subject numbers, when you’re signing up.

How do you decide what riff to choose? Here are three approaches to consider:

1. Follow what you like. Do you like steak a lot? Maybe that’s a sign that your body needs more steak. Even if not, you would probably enjoy it. So why not sign up for a steak and potatoes riff? You might lose weight, and even if you don’t, you’ll be making an important scientific contribution while eating delicious foods you enjoy. 
2. Put your money where your mouth is. This is a chance to test your theoretical bone to pick, whatever that might be. If you think the potato diet works because it is low sugar, then potatoes + sugar shouldn’t work. You can try that and test your idea. If you think the potato diet works because it is a seed oil elimination diet, then potatoes + sunflower oil shouldn’t work, while potatoes + coconut oil should work as normal. You can recruit three friends and test it. You might be surprised. 
3. You can choose “randomly”. What sounds funny? What is no one else doing? Go with that. 

Anyways, to sign up: 

1. Fill out this google form, where you give us your basic demographics and contact info. You will assign yourself a subject number, which will keep your data anonymous in the future. You will also tell us what riff(s) you’re interested in. 
2. We will clone a version of this google sheet and share the clone with you. This will be your personal spreadsheet for recording your data over the course of the diet.
3. On the first day, weigh yourself in the morning. If you’re a “morning pooper”, measure yourself “after your first void”; if not, don’t worry about it. We don’t care if you wear pajamas or whatever, just keep it consistent. Note down your weight and the other measures (mood, energy, etc.) on the google sheet.
4. Do your version of the potato diet for at least four weeks.
5. When you reach the end of the diet (whether you’re ending the diet early, reaching the end of 4 weeks, or reaching the end of a longer span), send us an email. Let us know if you want to publish your results yourself (in which case send us a link to your post) or if you want to publish your results on SMTM as a philosophical transactions post (in which case send us a detailed email about your protocol, results, and thoughts).
6. Remember that it is ok to end the study early if you need to, for example if you get sick. It’s also fine to reach the end of 4 weeks and keep going if you’re having a good time. Just make your intentions clear in the comments on your data sheet and send us an email whenever you decide to finish, we’d love to hear from you.

We plan for this to be somewhat more relaxed and more casual than our previous studies, so please understand if we take a few days to sign you up or get back to you about anything.

As always, if you think this is an interesting idea, please tell your friends!