Can a Diet That Mimics Fasting Turn Back the Clock? | Hacker News Reader

Can a Diet That Mimics Fasting Turn Back the Clock?

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181 pointssjcsjc131 comments

I've been trying out fasting over the past 6 months or so. I watched the BBC documentary (Eat, Fast & Live Longer) and read Jason Fung's book (Complete Guide to Fasting) and decided I'd see if I could do it; mostly to lose weight but the health improvements often cited seemed great as well.

For me it turned out it to be easier to do than I thought. I had a mental barrier in my head that going without a meal or two would put me in some sort of dangerous state where my body couldn't function. Once I realized that wasn't the case I was able to plow through increasingly long periods of time without eating. Things I've noticed:

* being h-angry is a real thing. ;-) Make sure you have a low-stress time window to do the fasting in * drink a lot of water * hunger comes in waves, you'll get to a point where you feel super hungry, it'll usually pass after some time. * maybe it's placebo but I recognize a stronger ability to focus when I'm in the midst of a fasting period * if you get super hungry, just eat. don't beat yourself up over it * i've generally learned to NOT tell people you're fasting, they think you're crazy (immediately they associate it with anorexia, etc) * again, don't forget to drink water

I was diagnosed with prediabetes and hepatic steatosis 8 months ago. As per my doctor's recomendation, I followed by 3 months a ketogenic diet combined to a time restricted kind of intermittent fasting, which basically means that I started to skip breakfast. My glycose and insulin levels normalized and the liver fat went away.

I can't pinpoint which factor contributed the most, but I continue to do intermittent fasting skipping breakfasts. When I feel like it, I try to fast for 24h, usually 2 to 3 times a month. It really isn't that difficult, it just takes discipline and focus.

Regarding your advice, I'd like to add just a point: drink more water, true, but also try to increase your salt intake. It seems to make a lot of difference in the beginning, alleviating possible side effects.

I've never eaten breakfast, even when I was a child. Just not something my family has ever done. I somewhat often accidentally forget to eat for 24 hours. I wonder why I find this comparatively easy compared to what others have expressed?

Great to hear you had good results!!

Can't agree more. I have been following the LCHF movement, and the Intermittent Fasting by some prominent doctors (including Dr. Jason Fung). Fasting was difficult when I tried going without food for a day for the first time. However, now, when I have a busy day ahead and want to be energetic the following day, I just skip dinner the prior evening. I have also tried a full day fast and have felt good enough that I do this whenever my schedule permits. This [1] video convinced me to try fasting, and I am happy I tried.

[1]: https://www.youtube.com/watch?v=gBACh6c4zNY

Edit: Though the video starts off talking about a vegetarian diet, the main talk by Dr. Alan Goldhamer is about fasting, and has nothing to do with one's dietary choices.

I think the mental blockage is the main issue with dieting (what else should it be, really?). I've seen so many diets that try to be super smart and as a result complex. They are these "lifestyle" changes, comparable to becoming a vegan or something and I always figured that this is what dieting _is_ and, as a result, that I couldn't do it.

Turns out, simply cutting your calorie intake (while generally eating whatever type of food you like) works out fine and has minimal drawbacks. In fact, I felt less "bloated" (I know, that's a health food buzzword but it's kinda real), which more than counter-weighted the lack of comfort food. You also have to get used to the idea that "hunger" is a normal, everyday feeling and not an alarm signal (first world problems, right?). Usually, you can actually still _eat_ whenever you're hungry, anyway, and it even tastes better!

25-50% off is easy. You can eat a full meal, generally, and still be below your 50% daily calorie intake, there's still room for a snack. All supermarket foods have calorie labels now and the rest you can look up online and quickly get a hang for. We all know the worst offenders (chocolate, soft drinks, fried stuff,...) but once you look it up it forces you to face the reality of it. I never wrote down any lists, just a rough, rounded number in the back of my head.

Generally, it was way harder to start than to keep going. After a week or two, it's easy. Lost 10+ kilos that way over the course of a few months (like 4 or 5?), which put me within my personal weight goal.

Subjectively, I find it much easier to cut total calories by intermittent fasting than by willing myself to eat less once I've started a meal. And it also makes meals more rewarding and enjoyable for me, personally.

I don't know if it's the healthiest or most ideal way of going about it, but it's what works best for me.

That's one of Dr. Fung's arguments, there are a lot of creative diets that become reasonably complex etc and are hard to follow over the long run. He also points out the difficulty of portion control in the midst of a meal. Fasting is pretty simple as far as all of that goes. You don't eat.

In short, cut out the crap and you're most of the way there (to the reduction total). But if you think of sugar, etc. as necessary and natural then you're more or less doomed, as you deserve to be.

> Glucose is a ubiquitous fuel in biology. It is used as an energy source in most

> organisms, from bacteria to humans, through either aerobic respiration,

> anaerobic respiration, or fermentation. Glucose is the human body's key source

> of energy, through aerobic respiration, providing about 3.75 kilocalories (16

> kilojoules) of food energy per gram. Breakdown of carbohydrates (e.g. starch)

> yields mono- and disaccharides, most of which is glucose. Through glycolysis and

> later in the reactions of the citric acid cycle and oxidative phosphorylation,

> glucose is oxidized to eventually form CO2 and water, yielding energy mostly in

> the form of ATP. The insulin reaction, and other mechanisms, regulate the

> concentration of glucose in the blood.

Sugar breaks down to equal parts glucose and fructose though. And fructose is treated very differently from glucose in our bodies.

Do you care to elaborate on how they're differently treated?

Glucose is used as fuel, whereas fructose doesn't have a direct pathway to be used as fuel, it must first be stored as fat.

You then have to have an absence of glucose in your body before you may metabolize your body fat. This doesn't happen often for most people, hence, the obesity epidemic from overconsumption of sugar.

That's the short version. The long, detailed version is available from YouTube, search for Dr. Robert Lustig's videos.

I'm sorry, but I don't understand the point of your comment.

Mine was, in short, reducing isn't so hard if you simply remove the unnecessary. That's it. Speaking for myself, as fit as I might be, I do know I consume unnecessaries.

No, you went on to say:

> But if you think of sugar, etc. as necessary and natural then you're more or less doomed, as you deserve to be.

Which, apart from being wildly unnecessary color commentary, is the equivalent of saying the earth is flat. Sugar is literally one of the core building blocks of aerobic life, which is over 99.9999999% of multicellular organisms.

The thing I learned from time-restricted IF --- which I've been doing pretty painlessly for ~2 years now --- is that I generally won't feel hungry until I eat for the first time every day. I started by skipping breakfast and waiting until 2PM for lunch, but over the last 6 months I've pushed 2PM forward to 6PM and eat just one meal a day.

I have friends who have noticed the same thing, and others who haven't. I'm sure it depends on your metabolism. For anyone not training who hasn't tried time-restriction, it's worth it: if your metabolism works like mine, not having to think at all about food except for ~4 hours of the day is super convenient.

>not having to think at all about food except for ~4 hours of the day is super convenient.

Interesting. Much earlier (teens), I had read a book - I think it was a story about Robin Hood - in which they said that he and his men ate only once or twice a day. I remember wondering at the time how it was possible, how they did not feel hungry, more so since they had active physical lives.

> maybe it's placebo but I recognize a stronger ability to focus when I'm in the midst of a fasting period

I vaguely recall a recent study that covered this. I believe the theory is that when we're hungry our brains become more focused to aide in our ability to find food. After we've eaten there's not much need to think.

To the greater arguments regarding intermittent fasting: I hate to call on the historical human argument, because it's often abused (e.g. for the raw food diet, paleo diet, etc), but in this case I think it applies because until very, very recently the vast majority of humans spent most of their lives hungry. Hell, we still have parts of our world today where people starve to death (not because of lack of food production, by the way; it's a political issue). It's no surprise, then, that not only can we go without food just fine, but a significant portion of our behaviors and adaptations are built around intermittent fasting.

That isn't to say that intermittent fasting is maximally optimal. It may just be more optimal then how most Americans eat (large meals 3+ times a day, occasional snacks and a sugary beverage throughout the day).

I think the biggest issue we face today is our food culture, particularly in Western societies. Food is the center of every occasion. In Latin derived families you see the habit of constantly forcing food on guests, and both Latin and Southern European cultures are big on forcing their children to eat until their plate is empty.

This made a lot of sense when food and calories wasn't abundant, and there has likely been a lot of selective pressures on those cultures over our recent history. But food is plentiful now. Whereas in the past when forcing children to eat every last speck meant them barely getting enough to eat; today forcing children to eat, eat, eat means making them fat.

Unfortunately I don't think the same selective pressures will work. Being overweight isn't going to stop you from raising a family. So our only two real solutions are to either forcefully change our cultures so that dieting, whatever the diet may be, is the cultural norm, or we apply science to develop foods with lower caloric densities. The latter is, unfortunately, demonized for some godforsaken reason (e.g. artificial sweeteners).

I saw this video called "Fasting vs. Eating Less: What's the Difference? (Science of Fasting)" just yesterday, and it's good to hear many of the points it raised validated by your experience:

https://www.youtube.com/watch?v=APZCfmgzoS0

> hunger comes in waves, you'll get to a point where you feel super hungry, it'll usually pass after some time

Matches what the video above talks about "Ghrelin" from 5:03 onwards.

I recently fasted for 5 days, and it was much easier than I expected. When I started, I didn't think I'd last 1 day, never mind 5 - but actually I could easily have gone longer!

I agree about hunger coming in waves; I'd go 12 hours without even thinking about food, then it's all I could think about for an hour. Probably didn't help that I was still cooking for the family!

Err, I don't think that not eating for five days straight is any kind of healthy, though.

What is this conjecture based on?

There is a lot of evidence to suggest that fasting, and even intermittent fasting, is a good thing (actually, I seem to recall some papers/articles have ended up on HN). Fasting has also been shown to regenerate the immune system[1]

Besides, I have enough body fat to supply calories for a good bit longer than 5 days :)

[1] https://news.usc.edu/63669/fasting-triggers-stem-cell-regene...

Depends who you ask. I did a 12 day fast once, nothing but water. I intended to do a 10 day fast, but I felt so wonderful, so healthy, so clear, that I decided to add 2 extra days.

For those interested, most of the benefits (for me) happened after the 5th day. Thats when the hunger and caffeine withdrawal ended.

I don't know all of the science behind it, but I can honestly say that I never felt better/healthier in my life.

3 days and your immune system "reboots." Not sure if anything after that helps but an extra day or two hardly sounds troubling.

Depends on the person. Angus Barbieri completed a 382 day medically supervised fast in 1966. Depending on body composition and physiology, one might reap a lot of benefit from simple intermittent fasting while another person might continue fasting for longer stretches to help reset their body to more normalized hormone levels.

As is often the case, it depends on the context. For someone obese and/or diabetic, extended fasts of 3-7 days as recommended by Dr. Fung can be very beneficial.

Why do you think that?

Can you describe your regimen, starting/ending weight, exercise habits, and general health status? I've considered not eating one day a week for general health reasons, but I am very thin, and it is hard for me to maintain weight even with 3 meals per day on a healthy diet.

5-6 days a week I eat twice a day. 1-2 days I fast. I normally don't eat breakfast. I go to the gym at least once a week, but normally not more than 2 times. I don't do cardio, I only lift weights. Blood tests etc are all in the normal ranges, no major (or minor) health problems. I don't have any good advice for maintaining weight since I'm on the opposite side of the spectrum. :( I lost a little more than 10% of my weight over 6 months; for my height my weight is average.

Are there any particular foods you avoid or ones that you eat more? Fruits for example, are you eating more or less of those? How many times a day do you eat and which meal do you skip? I'd like to hear more usable info about this if you don't mind me asking.

I generally try to avoid sugar and refined carbohydrates. I find if I eat too much of them my appetite spikes later in the day or the next day. So my "normal" diet low-carb, hight fat. I eat a lot of protein and vegetables but I'm not religious about it. If my family / friends want to go out for pizza or whatever, I'll have it, and dessert. :) But most days, except for those when I'm fasting, I usually eat chicken or fish and vegetables. I only eat breakfast once or twice a week (on the weekends with my family) and then it's just eggs and bacon, maybe a slice of toast. I fast a day or two a week. The meal plan for those days is simple: water and black coffee.

The most important - and as yet, unanswered - question I have about fasting is: are the benefits (if they exist) the result of absolute fasting or is relative fasting just as effective ?

If I require an extra 600 calories per day due to exercise, but I "fast" by cutting caloric intake by 15%, do I receive a comparable benefit to someone who does not exercise but also cuts their caloric intake by 15% ?

All evidence seems to point to exercise regimens as providing quite pronounced longevity benefits - equal to or greater than what we expect from fasting. But this is counterintuitive since exercise - and the calories it requires - represent an absolute increase in total metabolism.

So if we each fast our way down to the same trim and lean low calorie existence, but you are consuming 2000 of your previous 2500 calories and I am consuming 2400 out of my previous 3000 calories (assuming we are the same size, weight, etc.) who gets more longevity benefits ?

Valter Longo's research is essentially aiming to answer some of these questions. He was looking for the 80/20 point at which reduction in calories produces much the same outcome as fasting. His current position is expressed by the fasting mimicking diet; you might go read the papers in which he outlines trial results and the data that forms the basis for the diet.

From a gene expression in mice point of view, none of it is exactly the same. Different but overlapping patterns of change for calorie restriction, isocaloric intermittent fasting, intermittent fasting with calorie restriction, methionine or other protein restriction, etc, etc. All different.

Also, all the data on exercise shows it does little to life span in comparison to calorie restriction, while both are vaguely comparable when considering healthspan. There are plenty of papers on this topic to read. Again, completely different set of changes and benefits.

Not answering your question directly, but I don't think you can compare calorie restriction with fasting in that way. Over time, reducing calories by 15% just causes your body to lower its metabolic rate accordingly (see Biggest Loser contestants), while fasting turns off the digestive system completely, allowing the body to focus on other tasks. That's when you get benefits like persistent low insulin levels, autophagy, etc.

In other words, if you have 1000 calories to eat over two days, you're better off fasting entirely one day and eating the 1000 calories in one meal the second day rather than many small snacks over the two day period.

From an HN audience perspective, perhaps the most interesting thing going on here in recent years is the way in which Longo's group managed to break out of the funding ghetto of aging research for this one part of the field by figuring out the plan and establishing the relationships to productize the research. This pulled in new money and support that allowed them to make good, new steps in quantifying the effects of reduced calorie intake. The cost is that we now have another set of marketing drones extracting rent from the regulatory capture /intellectual property morass for telling people to eat less, but you can decide for yourself whether this is clever hacking of a hopelessly corrupt system or adding to the problem.

I've had great success with a pretty severe dieting routine. I eat a reasonable (800-1,000 calories) dinner as my only meal but also allow myself a cappuccino in the morning and all the carrots, celery and fresh fruit I want throughout the day. The main benefit for me is that it does not take a lot of thought. I can drop 4 lbs a week this way without any apparent negative health effects.

For reference, I'm a 41 year old male, in good health, weighing just under 200lbs at 6'3". I'm a software/hardware engineer so I spend much of my day sitting indoors.

How long do you do this for?

A few weeks at a time when I need to lose some weight.

how sustainable is this?

Doesn't have to be. As someone who's on a similar regimen, best part of the intermittent fasting is that once the body gets used to it you can stop/start at will. If my coworkers go out for lunch, so can I, even if it would technically violate my fasting period. Then I just go right back fasting the next day with no issue.

> There were no adverse effects on quality of life

Does quality of life have some specific medical meaning? I'd say not being able to eat as much would be a huge reduction in quality of life for myself and many people in know. No I don't massively over eat like many Americans but I love eating and cooking and going out to dinner. Trying to keep calories at or below 2000 is hard enough. I can't imagine having to try to enjoy even less.

From https://doi.org/10.1093/gerona/glv057

We found no significant adverse effects of CR [calorie restriction] on a broad range of quality of life variables including mood, self-reported hunger, sexual function, and cognitive function, using validated measures of all constructs. These results are shown in online Supplementary eTable 3.

> Trying to keep calories at or below 2000 is hard enough.

How much of a reduction from your baseline usage is 2000 kcal per day?

Well, the thing is your ideas and feelings might change after the fasting period, and you may end up thinking that it hasn’t negatively impacted your life.

It's actually quite easy after the first few days. Your body simply has to adjust to burning fat/glycogen. I've gone days when I've eaten maybe 500 calories and never felt hungry, but the first day I thought I was going to pass out. One thing you learn from fasting is to recognize when your body actually needs food vs when you just crave a blood-sugar-rush. What most people think of as "hungry" is really just a trained reflex, and it can be retrained. These days if I'm not active I can easily go at least 12 hours without feeling hungry.

Granted my job is sitting in a cube 9 hours a day with some scattered meetings. YMMV.

Okay, this is a small little trick but I found the easiest thing to do is to not eat in the morning. I can easily not eat till 10am without feeling hungry. Sometimes 11 without effort.

And then I stop eating early in the day... say 8pm or 9pm.

I found that to be very sustainable and easy in the long run. YMMV.

Do you work out or exercise at all? I can't see that working for folks that do. Or do you take any medications that might inhibit your hunger? For example Adderall tends to be an appetite suppressant.

You would be amazed at how much of the feeling of hunger is actually habituated, not your body actually needing energy.

A horrible experiment you could do, but should not, is to set an alarm for 1 AM. Get up and go eat some cookies or ice cream, and then go back to bed for 3 weeks.

Even if you have NEVER woken in the night because of hunger, you will now be EXTREMELY hungry every night, and naturally wake up to eat.

It was my experience that after skipping breakfast for about a month, I now never even desire it. I do get my recommended Total Calories for the day each day, which is what makes it easier to adapt.

8pm and 9pm are really late to "stop eating".

You find that late? Interesting. I am simply not hungry before 7pm.

I'm very much the opposite. My entire day is shifted forward a few hours so I'll generally wake around 5am, breakfast at 5.30. Lunch is around 11.30 and dinner at 5pm (latest 6). Bed around 8.

I hate sleeping during daylight hours so shift my day to make the most of it.

I currently do a very similar regime (sunrise is at 4:30ish, sunset 7ish at the moment): wake 4:30 ish, skip breakfast, eat a light meal 300ish kcal at 11, and then have dinner of some meat and veggies at ~4pm. 8 -- 8:30 bedtime.

It's really incredible since I have also shifted my work hours to 6 am -- 2-3 pm. It feels pretty good. I was doing a single-meal version of this regime for several months, but at one point my body started craving for a slight influx of calories at noon.

I feel that all sleeping recommendations should come with a tag that says if the recommender has kids or not.

It's annoying that there isn't enough research on calorie restricted diets to conclusively show the benefits and drawbacks.

Diet research is notoriously difficult. If you have a chance (and haven't alreadY) pick-up Gary Taubes book, "The Calorie Myth." Even if you don't agree with his conclusions he does a great job in explaining the difficulty of diet research. It's why he prefaces ideas in his books with "I could be completely wrong about all of this." It's hard to completely trust any given study in the area and why there is a ton of conflicting information out there.

Intermittent fasting does not necessarily entail calorie restriction. However, if low calorie diets work one mechanism is probably autophagy, and intermittent fasting with much more moderate calorie restriction (or without calorie restriction) will also stimulate autophagy. So one could potentially get some of the benefits of calorie restriction while avoiding some of the problems.

All this said, fasting is an extra stressor on the body, I think... something to be aware of.

Autophagy can also be achieved by limiting protein over a certain time window, and some have advocated this as a likely preventative for diseases like Parkinson's and Alzehiemer's, involving "plaques" that are normally cleaned up during authophagy.

Diet research is expensive because people are terrible at self reporting. Especially with something like calorie restriction.

To get good data you really need to monitor people 24 hours a day.

> To get good data you really need to monitor people 24 hours a day.

Unfortunately people love their privacy too much to make that happen.

We could also give incentives to prisoners for participating in health related studies. It gets a really bad wrap because of historical abuses, but it could really be a win/win.

All the prisoners would need to be separated and lose access to the commissary. They would probably be willing to trade their commissary for access to an XBox in their cell or something similar.

Then we can control exactly what they eat, and measure the effects of a calorie surplus or deficit over time. We could even give prisoners the same amount of calories but different macros, to finally prove the effects of a long term ketogenic diet are different than just calorie restriction.

The food would have to be more palatable than what they receive now, and they would have to agree to consume 100% of it and not try and trade with other prisoners. This probably involves a guard who watches them eat in their cells. It would be costly, but not nearly as expensive as the controlled environment studies in a hospital (metabolic wards) that Gary Taubes has done before.

I doubt it has to do with privacy, have you seen how many selfies are out there with food shots and stuff? Plus, such studies could be funded to give people money for tracking this.

I believe the problem isn't with privacy but just that it is difficult to keep notes of what you eat daily. Make a product that makes monitoring what you eat very easy to do and you can get more data that's solid. What Apple did with HealthKit did in fact help, we just need more of that. I know a buddy who lost weight easily because of a smartwatch (Apple Watch) that he uses to monitor his input because it is so easy and quick.

People should be more serious about nutrition. It's impossible to track and test nutrients if you're not disciplined about it.

Ideally, you would only eat what you (or a coach, or an app) planned to eat. Most people should have a nutrition routine where they eat the same thing every day or week. Eating for pleasure should be the exception, not the norm. Tracking only the 5% of food that's not part of your routine would be a lot easier (especially if packaged and provides a bar code).

No, people should be less neurotic about their nutrition, eat less, and let go. Don't over think it or put up barriers to health.

Most people are not qualified to feed themselves.

This happens frequently. See: metabolic wards.

do you think there will ever be enough? calorie restriction is just one, very vague detail about input for human body; macro distribution, amount of fiber, amount of water and many more are just glossed over. total weight or even breakdown by tissue type on the other hand is a very simplistic measure of the "output". blood glucose, white/brown fat distribution, hormonal balance, basal metabolic rate, blood pressure and many more - all depend from long-term diet choices.

it's like trying to train a nn by providing 95% random noise with input and not bothering to understand 95% of output.

seems like taking everything into account is just too expensive.

There is decent evidence in rat studies. Ok, not human, but its a good start.

I seem to remember primate studies haven't been so conclusive.

The CALERIE study data seems pretty compelling to me. What more do you want?

Demonstrative evidence that shows meaningfully lower disease rates and longer life expectancy in calorie restricted cohorts of accurately tracked long term human trials.

That is basically what most people would love to see.

Unfortunately, studies like this are notoriously difficult to run due to terrible self reporting. To complete an accurate study like this would likely take constant monitoring and an administered diet for the participants.

A few years ago I had some downtime and nothing going on, so I decided to try a water fast for three days as a sort of detox/cleanse after doing some research.

The first 24-36 hours were definitely the toughest, but then the hunger feeling just went away. It was sort of liberating in a sense that I didn't feel "dependent" on food for those three days; the key being to stay plenty hydrated. However, if you're currently working or going to school, I wouldn't recommend it. Save it for a time where you're mentally ready to take on that challenge. Coupled with low-stress and lots of rest, the results were pretty remarkable.

And from the article and science standpoint of it, it makes sense; the less your body has to spend time digesting food (say every couple hours with snacks/meals), the more your immune system can work and more time for the body to naturally repair itself. This is also why I try to avoid eating late at night.

There is no science to support the notion of detoxifying or cleansing[1]. Not eating does not cause your body to repair itself. There is no relationship between the time taken for digestion and your immune system. It's not like your body can only do one thing at a time.

By all means, if fasting makes you feel good or whatever then continue to do it. Just realise that none of your stated claims of its physical benefits are true.

[1] https://www.theguardian.com/lifeandstyle/2014/dec/05/detox-m...

Not eating absolutely causes the body to repair itself -- there are many peer-reviewed journal articles covering animal and human clinical trials that demonstrate this (a google scholar search returns huge numbers of results, but here are just a couple examples: http://www.sciencedirect.com/science/article/pii/S1550413115..., https://news.usc.edu/63669/fasting-triggers-stem-cell-regene...).

The words were: "as a sort of detox/cleanse" There are things your body cannot do, for example eliminating a molecule longer than some threshold.

That is why the pharma industry insists on using small molecules and why beta-amyloids (and others) are a huge problem.

Another datapoint: I've done a 48 hour fast and I felt hungry the whole time. However, the hunger sort of plateaued and then didn't contiune to get worse. It was sort of like, "Oh, I'm hungry. That's unfortunate. Time to continue with my day."

I did a six-day water fast and felt the same way.

Water only for four days, water with some lemon squeezed in for two more days.

Like you said, my hunger plateaued after 1-2 days. I just got weaker by the end.

Interestingly, the last couple days I found myself really enjoying watching the Food Network. My friends asked why I was torturing myself watching it, but it wasn't, I felt strangely sedated watching all kinds of delicious food being prepared and cooked.

Calorie restriction diets don't make sense to me the way they are phrased. Reduce calories by 20-50%...of what. My current calories? Of the RDA 2000? Cause the thing is the logical conclusion of this prescription is you eat approaching zero calories. If you're in a negative energy state you lose weight. Then your body adapts. Then what....restrict by another 20-50%? Maybe I'm missing something but the way metabolisms work is any calorie level you set the body will adapt to, and that number is different for every single person.

The amount of calories you burn per day is correlated with your weight. If you decrease your calorie intake by 20% you will lose weight until you reach the balance point where the new weight burns 20% less calories than your original diet. As long as you continue to maintain the reduced calorie intake you will continue to maintain your new weight.

There's more nuance than just that of course, but those are the broad strokes.

Your body will adapt but it's not going to just use 500 calories less than baseline in a week. It's not that difficult. Restrict calories to 500 less than baseline than after a week or two ifnyou haven't lost anything drop by another 250. Rinse and repeat. Extremely simple and easy

2000 calories is not an RDA; the average American needs significantly more, and spreading the impression 2000kcal is an RDA is dangerous. Actual calorie needs depend on age, height, weight, and activity level, and are calculated using the Harris-Benedict equation.

It's not an RDA but the average American probably does land close to 2000 calories/day. Don't forget that half of Americans are women and that most Americans are sedentary.

anecdata of a single point, but I'm pretty typical. Early 40s male, fairly sedentary lifestyle. Whenever I try to figure out my baseline caloric level by keeping track of calories and watching how my mass increases or decreases, I always end up in the upper 2Ks.

Despite being overweight I'll grant you that my metabolism might be on the fast side, but I'm certainly not exercising the calories away.

I lift weights 3 times a weak. Early 40's male. Other than my weight lifting I lead a fairly sedentary style. My baseline is <2k.

When I was lifting 5 times a week and actively seeking to add weight, my average intake was 2400kcal.

To me what you describe doesn't sound typical at all, unless you're huge (I'm about 240lbs; and far more of that than average is muscle, which burns (marginally) more calories).

That seems odd. I'm in my 20s and do bodybuilding. I have a very dialed in eating schedule. My maintenance is around 2700-2800 calories but I lift 6 days a week plus cardio. I find it very odd that you could maintain weight at >2500 calories living a sedentary life and not having a clean diet.

Depends on the body size. Unless you are doing heavy physical labor, most energy is spent on maintaining body temperature and running regular chemical reactions in the body. Both depend on the amount of the body to heat up and to react in.

When I was in my early-mid 20s, my baseline was closer to 3000-3200. It's possible my metabolism runs high, was just throwing it out there due to the comment that it's possible our view of normal is skewed low.

I just got my calorie need measured as part of a dexa scan.I'm 6'3", around 200lb and my need is 1600 calories/day before activity. High 2000s sounds really high unless you are significantly larger than me.

I'm more like 6' and 200. I'm just going by how my weight fluctuates when I track caloric intake.

Depending on what resources you trust, the average does seem to land above 2000, but not wildly so.

http://www.webmd.com/diet/features/estimated-calorie-require...

Here sedentary women peak around 2k and sedentary men at 2.4k. In the 30-50 age group, its 1.8k and 2.2k.

Some tricks I've tried: --> Start the fast in the early evening before a long day of flight travel. Seems easier and convenient to avoid bad airport/flight food. --> Don't do it as a regular scheduled event. --> Eat according to your physical activity. Some days where Im just working in the computer I don't eat much. --> Do frequent random 10pm - 2pm next day fasts.

I've experimented with Keto many times, the first time I lost about 15lbs (granted I was working a warehouse job at the same time so that had a lot to do with it). Every subsequent time I've tried Keto I've developed a nasty rash on my back which has caused me to break out of ketosis though.

Today is my third day on Keto and I feel like crap right now. Apparently this is pretty normal and it goes away, and it has something to do with too low sodium intake. This comment has no real point, I just wanted to share.

When I do keto I make sure to drink at least one cup of bone broth every day, generally with some extra salt thrown in.

Whenever I do that, I manage to avoid keto flu.

Apparently, this is caused by ketones in the sweat.

I've also read it can be caused by histamines stored in bodyfat.

Wouldn't that inhibit rash swelling?

This was mentioned on HN not too long ago: https://prolonfmd.com/ (fasting mimicking diet). If they'd ship to where I live I'd try it. Always happy to try new things that could potentially benefit.

That URL is mentioned in the article. The site requires you to fill out a survey to see the cost. For the curious:

1-2 boxes: $299 per box

One box of ProLon is a 5-day total diet replacement. No extra food purchases needed for those days.

3-6 boxes: $250 per box

Using three boxes of ProLon over a three month period replicates the clinical trial protocol.

Price includes shipping, sales tax charged only in CA.

Holy overpriced batman! Are they feeding you with gold dust or something?

If you want to try this the frugal way, check out what this guy did.

https://www.quantifiedbob.com/2016/04/fasting-mimicking-diet...

Why couldn't I just drink water and electrolytes instead?

I recall an interview with Valter Longo in which he said the fasting-mimicking diet was just because patients were more comfortable with eating a special diet than with a full water fast, and doctors were also more willing to recommend the FMD than a water fast, because it seems so extreme to people.

So you certainly can just do a water fast instead.

There was a article a couple months back about fasting (3 days) and how it triggers a reboot of the immune system.

I think if you stop looking at calorie restriction as restriction, and instead consider it normal (i.e., the ideal the body prefers) then the current normal is essential over-eating.

That that a step further and consider such excess unnecessary stress on the body and it's various subsystems, things fall into place.

Factor in the various chemicals in today's food and it's not crazy to think we're eating ourselves ill - both from quantity and (lack of) quality (i.e., chemicals).

Pardon the editorial, but God only knows what GMOs do, to the body and the gut, under these circumstances.

> Pardon the editorial, but God only knows what GMOs do, to the body and the gut, under these circumstances.

I agree with most of what you said but the jury is still out on GMOs. GMOs are not just one thing either. Some may prove to be bad for us and others beneficial. The biggest problem with the anti-GMO campaign is that it's driving force is a general distrust of science rather than facts.

I know someone in the GMO field. I've asked him about gut bacteria. The reply was, "Good question. Big issue right now..." That's from the (private) horse's mouth. Yet I haven't seen that in anything I've read. That concerns me.

Perhaps. But the problem with the pro-GMO side is you can't say something is safe when you haven't fully tested it. Specifically, I'm speaking about gut bacteria - in humans and up and down the food chain.

We are in the early days of knowledge about the gut, and how it effects the entire system. So it's just not possible to test for safety. Sure you can eat it. You don't die. That doesn't mean you should.

GMOs are about yield and farming. They're not about humans, nutrition, and the gut. That's the context that can not be dismissed.

If you really think gut bacteria are important then maybe you should go get a stool transplant. We just don't know and the immediate assumption that GMOs are guilty until proven innocent is both uninformed and counterproductive.

I think it's more a distrust of the commercial entities involved rather than the science.

>then the current normal is essential over-eating.

It definitely is, but it's very insidious, because it doesn't /look/ like overeating. One of the things I've learned from following calorie restriction diets is that most of the food we eat is crazily calorie-dense.

You can get 30% of your entire required daily calorie intake from a salami and cheese sandwich. Now, some of that is the pepperoni and some is the sauce, but a huge amount of it is just the single slice of bread. In case you're wording, 1 slice of bread is about 5% of your daily required intake, which makes a sandwich 10% before you even talk about fillings.

If governments really want to reduce obesity in the west, they need to pass laws aimed at getting food with low calorie counts on the shelves. You can certainly make food with low calorie counts yourself, but who has the time? To make a difference, that shit needs to be as easy, cheap and available to buy as a microwavable lasagna (~40% of your daily calorie requirements). 90% of my problems with dieting are the mental stress of having to hand-calculate calories constantly and dive deep into the recesses of supermarkets to find things I can fit into the diet.

Well, in the case of bread (read: gluten) it's really the effects on glycemic index that's harmful.

This is what gets lost in the gluten free discuss. Gluten is bad for you. You might not be intolerent, but it'll still hurt you.

>Well, in the case of bread (read: gluten) it's really the effects on glycemic index that's harmful.

That's extremely true, although it was corn that was the real eye-opener for me. Corn based products have an even higher GI, and once again, they slip in all over the place, and this is in europe. It must be a nightmare to avoid it in the US.

I fasted for the first time after seeing some research on the benefits. Once I realized it's safe I figured, why not try and see how it affects me. I noticed a definite improvement in stress over the week following and now I try to fast once every 3 weeks if it fits into my schedule. Everyone reacts so differently to different diets I've found the most benefit from trying whatever I can and being mindful about the changes. We've become a little too obsessed with the one fits all approach to health.(e.x. Soylent) There is benefit to finding general guidelines through research, but a little self experimentation goes a long way.

I naturally fast once in a while. I almost always skip breakfast and eat twice a day. I was always curious why we eat 3 times a day, when we feed most pets twice a day.

Normally, once a month I'll have a lazy day, where I only eat from 6pm to midnight. I'll still have two meals, just closer to each other, one at 6pm, one at say 11pm before sleeping. Next morning I'll skip breakfast again.

That's just the way it works out for me. Not actually trying. Good to know this might in fact be healthy.

I eat breakfast and lunch, basically eat whatever I want between 8am and 2pm, and only water outside those hours. It was hard for my stomach to adjust for the first week (hunger pains) but no problems since

I posted the following as a reply a few weeks ago, but it might interest some people so I'll re-post it here.

Caveat - this is my interpretation of the various research pieces I've come across. I might be wrong.

It seems that having some period of starvation that is beneficial. Overall calorie intake is less relevant. Decreased overall caloric intake may actually be bad (can't find a link for this at the moment).

Benefits appear to include decreased risk of heart disease, type 2 diabetes and metabolic syndrome, possible decreased cancer risk, and decreased risk of neurological disease. Also longer life expectancy in some animals, as yet unproven in humans.

Even fasting for short periods regularly appears to be beneficial [5]

Three main reasons - autophagy, ketosis and decreased inflammation.

Autophagy, a kind of intracellular recycling operation, is increased by, inter alia, starvation [1]. It seems likely that most of the benefits of fasting derive from this. Valter Longo is a key researcher into this. Of particular interest to me is his work on fasting coupled with chemotherapy. [2]

Ketosis occurs when all your glucose and glycogen (a polymer of glucose) are used up, and you burn fat instead. Mark Mattson is a key researcher into this. Ketosis appears to have a neuroprotective action [3]

Decreased inflammation - chronic inflammation appears to be a cause of all sorts of problems, and fasting appears to decrease it.

[4] is a good general review

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2831538/

[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3608686/

[3] http://www.sciencedirect.com/science/article/pii/S0165017308...

[4] http://www.sciencedirect.com/science/article/pii/S1550413113...

[5] http://www.medscape.com/viewarticle/861319

Use sci-hub for paywalled papers.

Experimenting with the keto diet for my YouTube endeavors and one thing I didn't expect is how much better my joints would feel.

Prediction: the keto diet will soon come under HEAVY fire from mainstream media, journals, and lobbyist health organizations under the pressure of certain agriculture and pharma groups. Just wait for it.

Why would "keto" come under fire now? I'm pretty sure that diet already peaked and is on the decline.

The whole food industry is based around carbs [especially here in US, where you have corn syrup even in meat]. The dietary recommendations in US are still based around eating low fat [0] instead of massively limiting carbs.

However study after study shows that "keto" and IF (intermittent fasting) is probably the way to go. So now it's a pretty uphill battle. Seems like millennials are pushing for change more quickly and many massive corporations are changing directions, but slowly. So I think we will see a massive dietary change in next 20-30 years, but it's going to be a battle.

[0] https://health.gov/dietaryguidelines/2015/guidelines/executi...

> especially here in US, where you have corn syrup even in meat

What?

> However study after study shows that "keto" and IF (intermittent fasting) is probably the way to go.

Eh, I don't know about that. Some studies indicate that keto helps some people. But like every other diet, adherence is low. And for the most part, the evidence is that what most people need is to just eat a reasonable amount of something approximating real food.

IF is entirely unrelated to keto.

> So I think we will see a massive dietary change in next 20-30 years

I'm extremely doubtful. I'm doubtful we'll even significantly cut the junk intake. I have no expectation that keto will actually become common.

>> especially here in US, where you have corn syrup even in meat > What?

I meant meat products, like sausages, bacon, ...

> And for the most part, the evidence is that what most people need is to just eat a reasonable amount of something approximating real food.

I'm talking about the impact of the diet in overall, e.g. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1325029/

> I have no expectation that keto will actually become common.

I'm not talking about keto but dietary changes overall.

> I meant meat products, like sausages, bacon, ...

So like everywhere else, then? Sugar in cured meats is not exclusively an American phenomenon.

> I'm talking about the impact of the diet in overall, e.g. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1325029/*

I don't really understand your point. The fact that keto helps with diabetes isn't very relevant to a lot of the population.

> I'm not talking about keto but dietary changes overall.*

? The topic was about keto being "under fire".

> So like everywhere else, then? Sugar in cured meats is not exclusively an American phenomenon.

Not exclusively but definitely most prevalent in US

> I don't really understand your point. The fact that keto helps with diabetes isn't very relevant to a lot of the population.

A lot of population, like 10%? [0]. And this is just one of many. It's not only form of help but prevention. Meaning, it's much healthier for people to do keto, than anything else.

> ? The topic was about keto being "under fire".

And I made a comment on overall dietary change. We don't know what a long time on keto will cause, but I believe people are much more eager to experiment and see than they used to.

[0] http://www.diabetes.org/diabetes-basics/statistics/

You are right about the trends, but consider this.

The diet became extremely popular in the early 2000's, but among the "fad diet" mainstream population. That peak was unnatural, and most of these dieters will fail at whatever the new diet is because they have unrealistic expectations and don't really follow a disciplined program.

The diet is becoming more popular from a group that has a more scientific approach now.

Also when they diet began to decline there ALREADY WAS a huge push from certain groups to discredit the diet. When Dr. Atkins died he was fat, but this is anecdotal, what is crazy is that his autopsy was released illegally without the families permission.

From what I've seen Keto has started to expand beyond the "diet" label. It's become a universal nutritional description for no low carb, moderate protein, high fat eating, which I and a lot of my friends view as a permanent lifestyle choice (not necessarily inclusive of constant nutritional ketosis), similar to being vegetarian or vegan. When I hear someone describe themselves as a vegetarian I don't think of it as a diet, although I guess there isn't a better word to use to differentiate permanent versus temporary changes to the menu.

You haven't checked Google Trends lately, apparently....

The keto diet, and low-carb diets in general, already are under heavy fire from the mainstream media. Said media often cites government studies funded by said Big Agra / Big Pharma lobbies.

Big Corn is infinitely more powerful than Big Tobacco, and arguably more dangerous.

The AHA coconut oil nonsense is just the start of it.

I'm waiting for that as well. The science gets in the way of profits.

I've tried intermittent fasting as a weight control strategy. Unfortunately I discovered that fasting increased the frequency of my migraines. Fasting probably isn't for everyone.

I keep seeing advice in the comments to skip breakfast and how great it is.

What about the common folk advice of "eat a hearty breakfast by yourself, share a lunch with friends and give dinner to your enemy"?

The key as I understand it is a period of fasting [no eating] for 16 to 20 hours a day. Your saying would work because the last thing you eat would be around midday and you wouldn't eat again until morning.

I think that many people find it easier to extend their overnight fast by skipping breakfast rather than dinner in the evening. In the United States it is also true that breakfast tends to be more of a solitary meal and dinner more of a communal meal. So by skipping breakfast one is not as out of sync with family and friends who want to include you in dinner plans.

Probably not, but it can help us feel like we have some control over our own inevitable death.

yes

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