So I only ate potatoes for 2 weeks

https://www.petercai.com/so-i-only-ate-potatoes-for-2-weeks/

by squidhunter • 3 years ago

81 114 3 years ago

petercai.com

glanzwulf2• 3 years ago

"Po-ta-toes! Boil em, mash em, stick em in a stew!"

Fun experiment but for me crazy, specifically this part:

some days we were losing almost a pound of bodyweight due to ingesting only ~500 calories

Can't even imagine only eating 500 calories in one day.

kevviiinn8• 3 years ago

Not sustainable at all, the weight will more than likely come back super fast. A diet is something that you should be able to sustain over a long term

JBorrow• 3 years ago

In TFA they state that the weight loss was an incidental part of the experiment and in fact they thought they would gain weight.

tekla4• 3 years ago

Try it. Ive done 1 week water and coffee only fasts. You stop being hungry after 3 days or so

JoeAltmaier• 3 years ago

Same experience. For colonoscopies, instead of all the drugs I just don't eat for three or four days. Stop being hungry late on the 2nd day. Eating after that is just habit, trying to remember not to graze.

stronglikedan2• 3 years ago

Try it, yes, but only if you have sufficient fat stores, lest you lose muscle instead.

glanzwulf2• 3 years ago

What would you say is the best benefit for you?

stronglikedan2• 3 years ago

500 calories in one day

Especially since they weren't looking to lose weight, since they were not obese. It's likely the weight loss was due to muscle loss, and not fat loss.

itsoktocry4• 3 years ago

It's likely the weight loss was due to muscle loss

You think your muscle is deteriorating within days of a caloric deficit?

nervousvarun• 3 years ago

As someone who regularly does 24-36 hour fasts (alternate day fasting), it's not as difficult as you'd think. For me at least some of the weird/unexpected side-effects (insomnia being my major one) are harder to deal with than the hunger pains. I generally will have less energy at the gym on fast days but even that can vary and you have more than you'd expect.

One thing I've come to learn from doing this for years is our bodies really accept fasting well...which makes sense from an evolutionary perspective. We really are "built" to fast.

joenot443• 3 years ago

Nice writeup. I'd love to hear from some others who've tried this route for weight loss, the author certainly feels it could be promising.

It also led me to read a bit about "Sensory Specific Satiety" which is something I'd anecdotally observed, but now realize is well studied and understood. https://en.wikipedia.org/wiki/Sensory-specific_satiety

bell-cot• 3 years ago

Theory: In some old "hunter/gatherer" parts of the human body, an all-potato diet scores: [X] plentiful; [X] nutritious; [X] highly non-perishable. So there is sure to be ample good food available for a long time, and no need for an extra-body-fat insurance policy.

It would be interesting to test whether other all-starchy-root-veggies diets had similar effects.

astronads• 3 years ago

He admits in the article he was eating only ~500 calories per day. Of course he’s going to lose weight…

causi2• 3 years ago

I'd like somebody to write a browser extension that, a la Sponsorblock, lets a group of likeminded individuals flag and filter out for each other HN submissions for a wider variety of reasons than are permitted under the official guidelines. Reasons like "bullshit headline" or "article is a total lie" or "wild conflict of interest".

itsoktocry4• 3 years ago

lets a group of likeminded individuals flag and filter out for each other HN submissions

Yeah! You can call it MyEchoChamber or something.

tekla4• 3 years ago

If you follow HN, calories don't matter and is a made up thing that is completely irrelevant to weight gain/loss.

meindnoch3• 3 years ago

Coincidentally this opinion is usually held by Americans, who massively underestimate their caloric intake.

sethammons2• 3 years ago

it is not that CI/CO is made up, it is that your metabolism is a dynamic system. You can't beat CI/CO, but the value of CO changes based on CI and other factors such as activity level. You can't keep CO steady if you adjust CI because your body adjusts. The one that blows people's minds is you _can_ increase CI and maintain your activities and _lose_ weight. The cause is increased metabolism based on the kinds and frequency of foods you eat. Body builders have been doing exactly that for years.

axus• 3 years ago

I think his argument was that with potato-only he only wanted to eat 500 calories per day. For any other -only diet, he'd want to eat more than that.

tsgagnon3• 3 years ago

I think his argument was that with potato-only he only wanted to eat 500 calories per day.

For two weeks. Which is effectively nothing when you are talking about long-term issues like nutrition, health, weight, etc.

mizzack4• 3 years ago

Even ad libitum, the low palatibility and high satiety of potatoes makes you reach a point where you simply do not want to eat any more. For most people that yields a significant caloric deficit.

I did this experiment and it was boring more than anything. Plenty full/satisfied/not hungry, though.

twelve40• 3 years ago

did you feel like you maintained a decent energy level or spiral into a permanent malnourished slump? that's what i'm curious about, to me that's the biggest downside of calorie restrictions

itsoktocry4• 3 years ago

He admits in the article he was eating only ~500 calories per day.

If you can eat 500 calories of potatoes daily and feel satiated, why isn't that relevant?

rorytbyrne3• 3 years ago

Potato was the only food eaten by the majority of Irish people, up until 1848.

An average man ate up to 60 potatoes per day.

DoreenMichele• 3 years ago

Yeah, potatoes are like the only food I know of that a human can just about live off of successfully.

If we were serious about going to Mars, there would be more research into growing potatoes on Mars:

https://news.ycombinator.com/item?id=13823275

Just sayin'.

elchief3• 3 years ago

and after ~1590 of course, when the potato was introduced to the British Isles

rorytbyrne3• 3 years ago

Excuse me, the what now?

TMWNN• 3 years ago

By the 1800s, the potato had become the staple crop in the poorest regions. More than three million Irish peasants subsisted solely on the vegetable which is rich in protein, carbohydrates, minerals, and vitamins such as riboflavin, niacin and Vitamin C. It is possible to stay healthy on a diet of potatoes alone. The Irish often drank a little buttermilk with their meal and sometimes used salt, cabbage, and fish as seasoning. Irish peasants were actually healthier than peasants in England or Europe where bread, far less nutritious, was the staple food.

<https://www.historyplace.com/worldhistory/famine/introductio...>

cglan• 3 years ago

I’ve basically replaced rice with potatoes as my goto carb. They have way more taste, and there’s way more you can do with them. That said, I’m always a little worried that they’re unhealthy bc they’re so damn tasty if you boil them and then roast them with a little oil. Who knows

Carrots also taste incredible when cooked exactly like potatoes. Really any root veggie slaps when boiled and then roasted

xeromal6• 3 years ago

The biggest negative to potatoes is their glucose bump they give you. A solid way to reduce that is to cook them once then cool to room temperature. When you reheat them in any way you want, they will cause less of a glucose spike.

xeromal6• 3 years ago

I have an engineer buddy that years past wanted to figure out every nutrient he needed in the smallest amount of variation possible. He had a spreadsheet of various foods, their nutrients, and the amounts needed to maintain his weight. His conclusion was that potatoes give you the most bang for your buck calorie to nutrient ratio. I have his old spreadsheets and just filtered out the other foods.

https://imgur.com/a/ka0FK18

Pretty amazing what they give you as a monofood!

kevviiinn8• 3 years ago

Why is a glucose spike bad for non diabetics

xeromal6• 3 years ago

I'm not a doctor, but I believe the best way to treat your body is not to have big swings in values in glucose. If your glucose is 70 and you spike it up to 150 every day, I believe it's just a lot of stress on your body's endocrine system.

Someone can definitely chime in and correct me though.

thefz3• 3 years ago

Glucose spike -> oh shit blood is full of sugar, pump out insulin -> blood is suddenly not full of sugar anymore -> feel like shit, want to eat again -> glucose spike...

Reason077• 3 years ago

I had a engineer co-worker once who did something similar, but it was due to a dietary restriction rather than cost optimization. He'd only eat bland food with no spices due to some stomach/digestive issue. His lunches, as far as I can remember, were always either potatoes with tomatoes or rice with tomatoes. (I don't recall him losing any weight on this diet. Possibly the opposite!)

xeromal6• 3 years ago

I always love a true engineer's approach to solving a problem. Their brains are fun to peak into.

ashwagary2• 3 years ago

He'd only eat bland food with no spices due to some stomach/digestive issue.

There is another method that involves focusing on food volumes rather than other restrictions.

The average stomach can hold 8 cups of solid food but intestines can comfortably only process 2-3 cups of food at a time (every 4-6 hours).

The method works for stomachs with faulty fill guages. Fast food meal portion sizes, processed foods, and some medications are really good at breaking the reliability of these guages which is part of the reason for weight issues in western populations, atleast that's the theory behind this approach.

suprjami4• 3 years ago

That's amusing. Tomatoes used to be considered a low-FODMAP non-irritant, but Monash (leaders in IBS research) looked a second time and found that was wrong. A small as one slice of tomato can set off an IBS irritation episode in some people.

https://alittlebityummy.com/blog/changes-in-fodmap-ratings-f...

https://www.karlijnskitchen.com/en/monash-university-update-...

bmelton• 3 years ago

Food Theory[1] did a (sort of) scientific breakdown on this and came to a similar conclusion, which I think did a great of reinforcing the plausibility of The Martian

[1] https://www.youtube.com/watch?v=jg7DjKPoN1U

sn9• 3 years ago

Part of the reason the Irish Potato famine was so devastating is that you can get all of your nutrition from just potatoes and buttermilk.

Like plug it into a nutrition calculator and see for yourself.

Taikonerd• 3 years ago

If you're interested in trying This One Weird Trick, then the bloggers at Slime Mold Time Mold are recruiting for their "half-tato diet" study: [0]

The "half-tato diet" is one where you either get half your calories from potatoes, or half of your meals are entirely potato. (They allow either variant.) Their hypothesis is that half-tato is much more sustainable for the dieter than full-potato like the article above, and still quite effective for weight loss.

This is all based on a couple anecdotes, but I think SMTM would argue that an anecdote is a promising lead.

[0] https://slimemoldtimemold.com/2023/03/13/half-tato-diet-comm...

3pt141592• 3 years ago

In the long run you'll want to eat them with butter, not just boiling them. Otherwise there are some nutrients that you'll miss. Even so, potatoes cover a huge swath of the nutritional profile that a person needs. It's one of the reasons that potato famines are so devastating. Switching to grain flour alone doesn't make up for the difference.

mahathu• 3 years ago

Serious question because I am also interested in this, what about micronutrients in fruits/vegetables, fish etc.?

3pt141592• 3 years ago

I don't know why I was downvoted, but the answers you are looking for are available on a now offline website called WHFoods (World's Healthiest Foods) which you should be able to find on Archive.org or similar.

qwertox• 3 years ago

I don't manage to understand why the weight chart ist the first prominent piece of information. Eating only potatoes is barely good strategy for losing weight and only works because it is a too short duration to cause long-term damage (lack of other essential stuff).

ejb999• 3 years ago

Did the writer lose weight because they only ate potatoes? or because they only at 500 calories a day of potatoes - I suspect you could eat only 500 calories of almost anything and still lose weight.

matwood• 3 years ago

Enter the Twinkie diet: https://www.cnn.com/2010/HEALTH/11/08/twinkie.diet.professor...

thewataccount• 3 years ago

Yeah even assuming you're burning anywhere near 2000 calories a day, there's no way you aren't going to lose weight at a 1:4 calorie deficit. Even burning 1000 calories you're still at two times deficit...

rorytbyrne3• 3 years ago

I think the idea is that it's easy to eat only 500 calories, if the only food available is potatoes. Which should surprise absolutely no one.

xeromal6• 3 years ago

They make that point in the article. Potatoes are very filling. That's part of the allure. Try doing a diet of 500 calories of lettuce and you'll regret it.

When dieting, satiety is key and potatoes have that in spades.

voisin• 3 years ago

Try doing a diet of 500 calories of lettuce and you'll regret it.

Not sure this particular counter example is accurate. The volume of 500 calories of lettuce would be enormous and lead to satiety for other reasons (stretching of stomach).

mulligan2• 3 years ago

potatoes have that in spuds

mdrzn• 3 years ago

"People will eat more food if its tastier!"

Just eat bad-tasting foods for weeks and you'll lose the appetite! And you'll lose weight!

philipkglass• 3 years ago

This may be sarcastic, but I do think that modern obesity is partially driven by the availability of convenient "good tasting" foods. If you eat like typical Americans ate in 1960, then everyday meals are serviceable but don't tempt you to overeat from sheer deliciousness. Making delicious foods that you were tempted to overeat was more work, and often associated with holidays or other special occasions. But now we have foods that have been co-optimized for low cost and palatability that you can eat after heating for 3 minutes in the microwave oven. Overeating has never been more accessible or tempting.

matthewdgreen2• 3 years ago

Eating 500 calories per day is the challenge. It’s extremely hard for most people. The thing about eating potatoes (and I tried it for a week before I couldn’t stand things anymore) is that it basically kills your appetite. The very idea of eating becomes uninteresting. And it seems to go beyond the boredom: even adding seasonings and fried potatoes didn’t make much of a difference.

PartiallyTyped• 3 years ago

I found it easier to waterfast than to eat 0<N<1200 kcal.

wouldbecouldbe• 3 years ago

Yeah potatoes are just great because they have a very complete nutrient profile and pretty low in calories compared to weight.

Try eating 1.5 kilos of potatoes that will fill you up, still only about 1500 kilos (unless you go wild with the butter)

gonzo41• 3 years ago

Your suspicions are right! Calories are king. You can eat pretty much any junk food and your body will figure out how to get energy out of it. Eventually you adapt to whatever you have around you, and it that's all fast food, you're body will figure it out. Not getting fat is all about calories.

Though, there's no question you'll feel like shit doing it.

Dave_TRS• 3 years ago

Some studies show potatoes are the most satiating food, so one theory is eating them makes it more pleasant to stop eating generally and keep calories low (exact opposite of sugar, which makes one crave more food).

"Susanna Holt of the University of Sydney Australia did a research experiment in 1995 to compare the effects of different foods on short-term satiety and appetite levels. She prepared 240 cals portions of 38 different foods...The satiety index score she assigned to the potato was 323. No other food was even close. The second closest food was “ling fish” which scored 225." https://scottabelfitness.com/potato-and-the-satiety-index/

robocat• 3 years ago

The article addresses that 323 number:

  But separately from that, there has been frequent speculation that the outlier potato results in this study were at least partly because of their unappetizing preparation method -- boiled, cooled overnight and then microwaved before serving - which, coincidentally, would've raised their resistant starch levels, which we already suspect increases satiety.

mizzack4• 3 years ago

That's why the potato is superior. Eating 500 calories of hyperpalatable junk will leave you ravenous and wanting more (ever seen someone eat an entire large bag of chips?). With plain potatoes you reach satiety much quicker and you don't WANT to keep eating more.

Swizec• 3 years ago

There’s that professor who ate only McDonald’s, but added a daily walk to his routine. He lost weight.

https://www.al.com/entertainment/2015/08/meet_the_science_te...

Caveat: Losing weight is not necessarily the same as being healthier in this case

As for potatoes – I love using them as the carb in lunch. High volume, low calories, great combo. Makes you feel full but isn’t actually that much food. As a small person it’s easy to overeat in America so gotta be careful.

leephillips• 3 years ago

“Did the writer lose weight because [he] only ate potatoes? or because [he] only at[e] 500 calories a day of potatoes”

He’s quite clear that it was the calorie limitation, aided by the satiety effects of potatoes, and possibly the resistant starch factor. He considers other weird non-caloric theories (potassium, etc.) and finds them unlikely.

suprjami4• 3 years ago

Yes, this is the reason. It is repeatedly supported by the science of fad diets. See my other comment.

daenney• 3 years ago

I love how the author calls this a study, when:

* Sample size of 2, no controls whatsoever

* No actual scientific analysis or understanding of anything that's going on here, just a bunch of potato-adjacent studies and a few personal hypotheses

* Nothing got measured beyond weight, so who knows what this does to your health during those 2 weeks or what would happen longer-term if you'd stick to it

Please don't follow any kind of advice like this. The conclusion in the implications section that they've collected enough data to confirm the main hypothesis is equally nonsense.

They lost weight because they limited their caloric intake. That's part of what you need to do to lose weight.

kevviiinn8• 3 years ago

Not to mention they thought they would gain weight while eating 500kcal/day

tsgagnon3• 3 years ago

My favorite part is where they eat 500 calories of food each day but still state "Neither of us were looking to lose weight".

Or the comment on "So the fact that we ate exclusively one type of food most likely contributed to weight loss, but it's unlikely to be the whole story."

BigCryo• 3 years ago

Potatoes and other tubers have a low energy density and are conducive to weight loss

fullstop• 3 years ago

This reminds me of The Martian

AdmiralAsshat• 3 years ago

Add a daily multivitamin to it, and you have the diet from "The Martian".

doodpants• 3 years ago

Penn Jillette famously lost weight using an all-potato diet several years ago.

https://www.youtube.com/watch?v=NelIXCuuSZ0

armagon• 3 years ago

Do take a look at the results from the citizen scientists doing a potato diet study, and now a "half-tato" diet: https://slimemoldtimemold.com/2023/03/13/half-tato-diet-comm...

aredox4• 3 years ago

Another "making oneself miserable to lose weight" diet, that will be followed by a rebound as soon as it stops (which it will)...

Also note that potatoes are mostly highly assimilable sugars and as such make sugar blood levels spike - leading to diabetes long-term.

rwmj• 3 years ago

Could there be a kind of Taylorism going on here where the effect just happens because it's such a dramatic change to normal, and the effect will go away if the study continued for longer?

skocznymroczny• 3 years ago

(some days we were losing almost a pound of bodyweight due to ingesting only ~500 calories).

This is the key. There is no magic to lose weight. There are no magical ingredients and secret diet foods. Outside of some specific medical conditions, if you consume fewer calories than your body burns, over time you will lose weight.

Personally I am a fan of low-carb/keto/intermittent fasting diets, but there isn't much magic to them either, they are in the end a way to eat fewer calories. What food you eat makes a difference in terms of nutrients and satiation however.

It's possible to lose weight even eating only chocolate bars. Assuming 600kcal per chocolate bar, you can eat two chocolate bars a day and you should be losing weight. But chocolate bar is almost pure carbs, so it will play tricks on your sugar levels, make you experience mood shifts and you'll deprive your body of nutrients. And it won't take long until you start cheating when you keep getting hungry all the time.

Personally I wouldn't go for a potato only diet, because potatoes are carbohydrate heavy as well. I don't like the idea of eating only a single food. Eating the same meal every time might work better though. Something like fried chicken breast and broccoli or cauliflower is relatively low in calories and can keep you satiated for a long time, while also being a relatively healthy meal.

aredox4• 3 years ago

Short-term it is true, but long-term not: your body is adaptable and will adapt to lower caloric intake to maintain weight. This is why "you just have to reduce calorie intake" advice is shortsighted if not just plain dumb: if I eat less calories, is my weight going to fall down to zero? Of course not! (Save for real starvation, where one reduces intake below the body's ability to adapt)

It follows that one can lose weight without reducing calorie intake - and studies prove it: https://mobile.twitter.com/T_Fiolet/status/16435288286968176...

meindnoch3• 3 years ago

Huh?

Of course the answer is yes: if you keep eating 500 calories a day, like in the article, eventually you will die of starvation.

Starvation is less than 600kcal/day for the average person.

dave3332• 3 years ago

The Irish have subsisted on a mostly only potato diet for centuries which was fine until the blight took the entire crop.

aredox4• 3 years ago

You forget the beer.

sethammons2• 3 years ago

Due to being rather poor and slightly abandoned in high school, my major consistent food per day was a baked potato, no toppings aside salt and pepper. I hitched rides with a friend to school and back. I was on free lunch at school, I would try to steal an extra hamburger to sell for under a dollar, and that would allow me to buy a can of soup for dinner, heated over a wood burning stove. This was in Southern California around 20 years ago; time flies. Suffice it to say, I was not eating enough, malnutritioned, and it showed. Potatoes were my saving grace and I love them to this day. But they are not enough to stay healthy for months and/or years I think.

Zobat• 3 years ago

I hate to defend this kind of dieting because I don't believe in it, but as many seem to have skimmed the article and now think it says he/they only ate 500 kcal per day I want to add this snippet from the article.

"The addition of ketchup (and pan frying in oil) was for practicality, as we otherwise found it difficult to eat enough calories and lost weight too quickly (some days we were losing almost a pound of bodyweight due to ingesting only ~500 calories)."

hirundo• 3 years ago

It worked for me too until it didn't. I'm a world champion yo-yo dieter, having followed that jagged sinusoid from age 7 to 57, when I finally found one that keeps working. I've "succeeded" on more diets than anyone I've heard of. And then gained it back, often plus more.

I have notebooks and long spreadsheets full of detailed food logs that cover decades. They mostly show the same thing. Every diet works for me for weeks to months. The better ones work for six months or more. For me those included both raw vegan and low carb paleo.

I went hardcore potato as an accolite of Dr. John McDougall, a once quite popular high carb guru. I lost about 130 pounds on that program, and felt very wonderful. But without changing the kind of foods I ate, my appetite gradually recovered, and I gained all of the weight back and more over around a year. This was a mixed high-carb diet. I only went all potato for a month. I fell off of that just by getting very hungry for something else.

Bottom line, the study of satiety from any particular diet needs to be many months long to understand the full effect, and that can be very different than the short term effect.

elchief3• 3 years ago

I add a teaspoon of potato starch to my smoothies, and I find it makes it a bit more filling, and doesn't taste like anything.

Potato Starch is a Type II Resistant Starch, which is a nice pre-biotic to feed your gut microbiome

https://www.healthline.com/nutrition/resistant-starch-101

dave3332• 3 years ago

Potatoes are most easily cooked in a microwave - just poke a few holes with a fork and nuke for 5 minutes on high, maybe another minute or two if the potatoes are very large. The best way to fry them is in an air fryer. We cut yesterdays cooked potatoes into 1/4 inch thick rounds and spray with a little olive oil. We always eat the skins and all - I read someplace there are lots of nutrients in or near the skin. Salsa is a good alternative to ketchup for more flavor and less calories. Sweet potatoes and butternut squash are good alternatives to avoid the monotony.

zeeshanmh215• 3 years ago

I wish author share the metrics about fart frequency after having potatoes. I'm curious coz everytime I had oily food that contain potatoes, I used to fart more.

pcai2• 3 years ago

Author here. I will admit to having severe…let’s call it “gastrointestinal distress” the first 24 hours or so, until my body acclimated to the new diet. I would recommend easing into it over a few days, instead of the hard cutover I did.

Euphorbium• 3 years ago

I’ve done this for 2 days. It is was hard. Much harder than months that I ate only soylent analogue called Mana, which was not hard at all. But eating only potatoes is probably like 20 times cheaper.

suprjami4• 3 years ago

"I ate 500 calories of potatoes per day and lost weight. It must be because of the potatoes."

Considering even sedentary energy requirement is about 1800 calories per day, I have a shocking alternative theory.

Eating less makes you lose weight.

This concept of less-calories-in regardless of where they come from is repeatedly supported by science, read any fad diet article on Skeptoid: https://skeptoid.com/episodes/4664

pcai2• 3 years ago

Author here: I actually discuss theories for why ~500 calories ad libitum is satiating thus leading to weight loss. Your “shocking alternative theory” is already an embedded assumption and requires no discussion.

suprjami4• 3 years ago

Satiation vs hunger is a willpower issue, but I get your point.

876978095789789• 3 years ago

I think there's something to this. I added ketchup a few days into the diet because plain boiled potatoes were so unpalatable that it was difficult to otherwise eat enough, even when I should've been hungry given my starvation level of food intake (~500 calories worth of potatoes per day).

500 calories (a starvation diet) of potatoes, which provides about 13 grams of protein a day. I would love to see what before/after DEXA scans look like.

Why do "smart," scientifically-minded people do stuff like this? There's abundant evidence in the form of papers published by the most prominent researchers in the exercise physiology space (e.g., Aragon, Schoenfeld) about the importance of high protein intakes, even over 1g/lb, for the preservation of LBM during a prolonged deficit: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5470183/

Yet even people who meet these higher protein intake targets and do resistance training during their cut still lose muscle if they lose too much weight too fast. Why would you go on a diet that is both a starvation diet, and low in protein, and then blog about it proudly?

So I only ate potatoes for 2 weeks

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