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[question] Recommendations for fasting

4 Post author: Gunnar_Zarncke 30 August 2014 12:36AM

I consider fasting for two weeks in October, but I'm unclear about it being beneficial in general or for what kind of fasting it might be beneficial and healthy. Thus this is a kind of request for rational discussion of this topic.

I looked for relevant LW posts but couldn't find clear evidence. I think this is an underrepresented and possibly underutilized lifestyle intervention.

As a starter you might look at

Wikipedia has fasting and intermittent fasting. The latter shows

health benefits include stress resistance, increased insulin sensitivity, reduced morbidity, and increased life span.

But as I'm healthy and lean the benefits of intermittent fasting are likely small for me. What other benefits could there be?

I understand that body cleansing is not a real thing, but I wonder about the effects of fasting on the gut flora. Could it be that fastig has a beneficial effect on your gut bacteria? Just because your body doesn't get rid of any poison this way as the greeks believed doesn't mean that fasting has no cleansing effects at all. It could be that you get rid of some harmful gut bacteria or other parasites (not that these are frequent these days).

Another thing is that fasting might activate and kind of train metabolism cycles which the body may loose over time otherwise. For me it might be too late (I'm 41) for that (mouse experiments show fasting tolerance is plastic with age), but maybe not. On the other hand I'm not very likely to ever need the ability to deal with lack of food (except possibly in case of severe illness of injury).

Links on LW: Low hanging fruit: analyzing your nutrition and If calorie restriction works in humans, should we have observed it already? both mention intermittent fasting but I gain little insight from these.

Also related is Lifestyle interventions to increase longevity. (Intermittent) fasting is also mentioned on Mental rebooting your brain.

My current plan is to use Buchinger style fasting with fruit juice, thin vegetable broth and protein additions (which kind of protein I'm still unclear). I will reduce exercise to balance and walking level types.

I'm also unclear how to measure and track the effect of this diet. Sure I will track weight. But should I track satisaction somehow?

What do you think?

Comments (20)

Comment author: [deleted] 30 August 2014 09:00:05AM 6 points [-]

I've been fasting on alternate days for almost 2 months, limiting myself to 500cal on fasting days. I've stopped last week for a similar reason as why I've stopped bi-phasic sleeping schedule - both are incredibly fragile systems.

Under controlled enviroment, both worked incredibly well. I was stabilizing my weight, had increased energy, reduced mental load, general well-being (however quantifiable is that)... But once you miss that afternoon nap, or take those 500cal in the form of beers, everything breaks down. Something as simple as a doorbell at the wrong time destabilizes you for at least a day.

As to particulars of what I ate during that diet, I think that's to a large extent metabolism-specific (all nutrition is, imho), so you'll have to figure it out yourself.

Comment author: TylerJay 31 August 2014 07:29:58PM *  3 points [-]

I think it's highly likely that Autophagy is the most important effect of fasting. Here is a good article that explains the metabolic process if you're interested. In short, when you don't eat, your body cleans house and recycles junk in your cells like protein aggregates and damaged mitochondria. In the ancestral environment, people didn't eat ever waking hour so this process would presumably run pretty frequently. But now that we have food at our disposal all the time, it doesn't happen as much unless we make deliberate dietary interventions like fasting. Autophagy also occurs during chronic calorie restriction, which may account for its observed effects on longevity in mice. However, if we can get the benefit from a type of intermittent fasting without chronic CR, then that would be a net win because CR has many known harmful side effects such as lethargy and impaired thinking.

Personally, I do the LeanGains 16/8 fast/eat program every day. My feeding window is 12:30pm to 8:30pm and I don't eat at all outside that window. Within the window, I eat as much generally healthy food as I want. It feels great once you're used to it after a week or two (hormonal entrainment of meal patterns and all that), allows you to not worry about breakfast, and (hopefully) allows your body to clean up the intracellular junk better than if you don't do it. It can be sustained indefinitely without much effort and doesn't get in the way of anything else I want to do with my life. Just take the 80/20 or 90/10 rule to it and don't worry about it if you need to "break" it every once in a while. If you have company come visit and they want to have an early breakfast or a late dinner, then just do it and don't worry about it.

In my opinion, it's by far the most sustainable and least disruptive to lifestyle of the fasting protocols and I think that frequent mini-fasts like this are probably healthier and more effective than infrequent large/intense fasts. I encourage you to look into it.

Edit: I agree with others here. Fruit juice is liquid candy. Just eat whole fruit instead, primarily berries if possible as they have the lowest sugar(fuctose) to mass ratio and are packed with anthocyanins.

Comment author: Gunnar_Zarncke 31 August 2014 08:20:47PM 2 points [-]

This is a great recommendation. One that I will definitely try out. Actually it is close to what a friend of me seems to do instinctly.

The recommendation about fruit juice is accepted. For me personally it means little as I prepare fruit and vegetable regularly for the children and fruit juice (watered down) is rather a kind of extra.

Actually the latter may or may not fully apply to children which seem to have a much higher glucose demand:

http://science.slashdot.org/story/14/08/26/0036214/why-do-humans-grow-up-so-slowly-blame-the-brain

Comment author: TylerJay 01 September 2014 12:08:35AM 2 points [-]

Great! I think you'll like it. Let me know if you have any questions on that or just want any input on your plan in general before you start it. Feel free to PM me or we can Skype if you'd like.

Actually the latter may or may not fully apply to children which seem to have a much higher glucose demand:

While that's probably true as far as glucose is concerned, it's the fructose that often accompanies it which is the problem. In addition to the intermediaries and metabolites of Fructose being potentially harmful (fructose is processed more similarly to alcohol than to glucose), it also has little to no effect of satiety. Someone who has a glass of juice each day typically eats the same amount of other food, resulting in a net increase in their daily calorie intake.

Comment author: cameroncowan 30 August 2014 07:30:47PM 2 points [-]

I'm a big fan of "The Fast Diet" which advocates fasting 2 non consecutive days a week. I've lost weight on it and feel better.

Comment author: brazil84 30 August 2014 10:35:09AM 2 points [-]

My non-professional opinion is that much of the benefits of fasting come from what I call "running cool," i.e. eating so that you are at the bottom of your metabolic range. My thinking is that when you eat more than the minimum you need (but not so much more that you gain weight), the body adjusts by increasing its metabolic rate which puts more wear and tear on things and also leaves more energy free for mischief.

So that instead of fasting you might consider moderate calorie restriction -- you could call it micro-fasting between meals.

I'm also unclear how to measure and track the effect of this diet.

Yes, that's a real conundrum. Probably it can take years or even decades for the effects of one's diet to manifest themselves.

One idea I had is to regularly measure the uppermost frequency you find audible. Since this is know to decrease with age, perhaps it can be used to measure the rate at which you are aging. On the other hand, if you test yourself regularly in this way, possibly you will get better at perceiving high frequencies which would throw off your results.

Also, it might lead you into a lifestyle which is great for your hearing but otherwise counter-productive or even destructive. I believe Seth Roberts used to regularly test his ability to quickly do mental math and discovered great improvements from eating half a stick of butter a day. Until one day he had a heart attack and die.

Comment author: Gunnar_Zarncke 30 August 2014 02:06:12PM 2 points [-]

"running cool," i.e. eating so that you are at the bottom of your metabolic range.

I'm not sure whether I'm running cool, but usually I loose weight if I don't make sure that I eat enough. I don't feel hunger easily and on top of that I'm a picky eater. An enviable mutation in our society I guess.

Probably it can take years or even decades for the effects of one's diet to manifest themselves.

I didn't mean the effect of my overall diet. I'm quite confident that it's healthy. I meant the effect of the fasting. To reliably detect if something goes wrong quickly or slowly.

Comment author: brazil84 30 August 2014 06:46:21PM 1 point [-]

I'm not sure whether I'm running cool, but usually I loose weight if I don't make sure that I eat enough. I don't feel hunger easily and on top of that I'm a picky eater. An enviable mutation in our society I guess.

Yes, there's a huge problem with people whose natural instincts lead them to regularly overeat.

I didn't mean the effect of my overall diet. I'm quite confident that it's healthy. I meant the effect of the fasting. To reliably detect if something goes wrong quickly or slowly.

I would include fasting in the concept of one's diet. That's what I meant anyway.

Comment author: James_Miller 30 August 2014 02:26:20AM 2 points [-]

I have been doing Bulletproof Intermittent Fasting for over a year. For six days a week I try to limit my consumption of carbohydrates and protein to a six hour window. I do this in part by having in the morning coffee that contains MCT oil and butter from grass fed cows. My hope is that this is increasing my lifespan by significantly increasing autophagy. I am far from an expert on biology or nutrition, but from what I have read autophagy seems fantastically beneficial.

One immediate benefit I think I'm getting is that my colds are much more mild. I used to get colds that lasted 6-10 days and made me miserable. I could often tell I was getting a cold because my wife or son would usually get one first and then I would get a very dry throat. Since doing intermittent fasting my colds only last a few days and just make me feel a bit worse. I take this as a sign that I'm undergoing increased autophagy.

I twice did 24 hour fasts before I did intermittent fasting and both times I got a cold at the end of the fast. From what I have read this might have been because when you undergo a really long fast your body shuts down autophagy when the fast concludes.

I am keto-adapted, but the transition was difficult in part because I didn't know at the time that there might be a transition. Look up Atkins Flu to learn more about the transition.

Fruit Juice = Liquid Candy. Avoid!

Comment author: Gunnar_Zarncke 30 August 2014 02:08:33PM 1 point [-]

Fruit Juice = Liquid Candy. Avoid!

Some fasting regimens suggest fruit juice. I'm aware that it contain a lot of fructose, but for the duration of fasting (a 2-3 weeks) this seems to be an acceptable trade-off, or?

Comment author: James_Miller 30 August 2014 02:39:33PM *  3 points [-]

From what I know (but I'm far from an expert) having lots of sugar will undercut the goals you mention such as getting better gut flora and improving insulin reactions. I would strongly distrust any diet recommendations that include fruit juice.

Comment author: Gunnar_Zarncke 30 August 2014 02:44:31PM 2 points [-]

Could you qualify your distrust? Fasting is quite different to regular diet, so different rules may apply.

Comment author: James_Miller 30 August 2014 03:15:59PM 3 points [-]

You might be right. But from what I have read, sugar cuts against all of the reasonable goals of fasting such as getting better gut flora, improving insulin reactions, and becoming keto-adapted.

If your goal is to lose weight, paleo seems to work for lots of people, and a huge part of paleo is consuming very little sugar. I try to consume less than 30 grams a day. I started paleo when I was older then you are now.

Comment author: Gunnar_Zarncke 30 August 2014 06:38:03PM 1 point [-]

But from what I have read, sugar cuts against all of the reasonable goals of fasting such as getting better gut flora, improving insulin reactions, and becoming keto-adapted.

You might be right too. I didn't know that sugar negatively affects gut flora but I wouldn't be surprised. I'm not sure whether there is any need to improve insulin reactions. From my last consultation ('readings like a 19 year old') I'd guess that there is little room for improvement - but I surely wouldn't want to degrade my insulin cycle.

Im not clear whether the benefits of keto-adaptation outweight the disadvantages for me.

If your goal is to lose weight, paleo seems to work for lots of people, and a huge part of paleo is consuming very little sugar. I try to consume less than 30 grams a day. I started paleo when I was older then you are now.

It isn't. I'm lean and near optimum weight; I could just need a bit more exercise. My main goals are a) to learn how my body behaves under this regime and b) if possible to improve gut flora.

Comment author: James_Miller 30 August 2014 07:46:42PM 2 points [-]

Gut flora is really complicated and we don't know a huge amount about it. You should look into MCT oil as this purportedly positively effects gut flora. If you try it, however, go slow at first.

A good test as to your insulin reactions is to notice what happens if you don't eat until you have been up for, say, five hours. If you become consumed with hunger pains it's a sign of weakness. Your caveman body should be able to easily go this long without food unless your sugar-hungry gut flora have hijacked your brain to send you "feed us now!" signals.

Comment author: Gunnar_Zarncke 30 August 2014 09:35:57PM 1 point [-]

MCT oil is an intersting suggestion, but I will likely not try anything new here in combination with fasting - that is bound to create confounding which I wil be unable to unentangle.

Comment author: Gunnar_Zarncke 30 August 2014 09:34:12PM 1 point [-]

If I don't eat breakfast in the morning I don't develop any pronounced hunger until midday. But I notice that cycling or brisk walking without breakfast makes me feel somewhat weak (not that I'd develop hunger because of it).

Comment author: AnnaLeptikon 30 August 2014 06:23:36PM 1 point [-]

The general problem of fasting and extremely reduced intakes is that the metabolism slows down. Also you first lose a lot of muscles, then a bit of fat - when going on eating normal you burn less than before (because of less muscles) and therefore gain more fat. So for your body's composition I would say: Don't do it. (There is this great German book called "Die Physik des Abnehmens" = "the physics of weight loss" in which a physicist explains all this things very nicely)

However: I personally tried fasting for the mental effect, I was able to concentrate even better than normal, I liked the feeling of being "independent" from food and of being able to get through all of this things. (But I will not do it again because I try to get less body fat :) )

Comment author: falenas108 31 August 2014 08:58:32PM 0 points [-]

As a physicist, I would not trust a book about weight loss by a physicist unless they also studied nutrition at an academic level.

Actually, I wouldn't trust a book about weight loss by anyone who hasn't studied nutrition at an academic level, that field is incredibly hard and it's too easy to simplify.

Comment author: beserker1 04 September 2014 12:29:25AM 1 point [-]

I've tried intermittent fasting in the past. I mainly tried it, because I heard it helped with fat loss. It seemed to have a positive effect, and also helped my concentration skills.