Starving the Enemy



Join 36.9K other subscribers

I recently finished reading Perfect Health Diet:  Four Steps to Renewed Health, Youthful Vitality, and Long Life by Paul and Shou-Ching Jaminets. It’s a great book and I recommend it to all, who are not afraid of delving into the rather technical issues of health and diet. What I particularly liked about the book is that the Jaminets provide an on-line supplement for those interested in checking primary literature sources for various assertions they make.

Reading Perfect Health Diet reminded me of Transcend: Nine Steps to Living Well Forever by Ray Kurzweil, which I read a while ago (I guess boiling down complex and messy reality to a few ‘easy steps’ is a requirement, if you want your book to sell). It was a fascinating read, but ultimately it failed to get any traction with me, and did not change my life in any noticeable way. Two things were a complete turn-off. One was that the most important of Kurzweil’s nine steps was basically calorie restriction (CR). I am sure that CR extends life, but is it life worth living?


Rhesus monkeys Canto, 27, on a calorie-restricted diet (left), and Owen, 29, on an unrestricted diet (right), at the Wisconsin National Primate Research Center on May 28, 2009. Photograph by Jeff Miller. Source

Some years ago I saw these photographs of two monkeys in a CR study (see above). One (Owen, on the right) is fat and jolly. He ate as much as he wanted and he is going to die young. The other (Canto, on the left) is wan and sad. He is on a CR diet and he is clearly miserable. I almost can read it in his eyes: just give me some fat so that I could clog my arteries and leave this vale of sorrow.

The second thing that undermined Kurzweil’s agenda for me was his ‘engineering’ approach. According to him, the human body is merely a mechanism to be fixed. You push this button and get that result. He apparently spends a whole day once a week connected to a blood-filtering machine that takes out all the bad stuff out of his blood and puts in goodies, such as vitamins, etc. As a biologist and a specialist in nonlinear dynamics I wondered whether such a straightforward approach is really the one that works.

Consider this: if you want to stop being fat, you should eat less fat. Makes sense? Sure, but that’s linear thinking. In the nonlinear (read: real) world it’s wrong, and the Jaminets explain why. If you don’t eat fat and a myriad of essential nutrients that come with fatty foods, your body will be undernourished (in those essential nutrients), so you will be hungry all the time and will overeat on other foods, such as carbohydrates. In the end, you will get even fatter than you were before you went on the diet.

Yes, a tiny minority of people manages to lose weight on this diet, but most of us can’t. I tried it. It is very exhausting to constantly exercise your willpower. At some point your willpower sort-of ‘blinks,’ and suddenly you wake up shoveling ice-cream in your mouth – and you don’t even remember walking to the fridge and loading the bowl with ice-cream. Your subconscious (the “elephant” in Jon Haidt’s wonderful metaphor) took over and did it all without consulting you.

Another downside of a calorie restricted diet for me is that I need my willpower to get work done – I simply can’t afford to spend it all on preventing myself from ‘overeating.’ And most tellingly, people who succeed to starve themselves deprive their bodies of a host of essential micronutrients (read Perfect Health Diet for details). And, they usually continue eating poisonous foods like wheat and legumes. A really bad strategy. I am glad I never had enough willpower to go on the CR diet!

Unlike Transcend, Perfect Health Diet is infused with evolutionary thinking. The Jaminets eschew linear thinking and work through the feedback loops and trace out unintended consequences, so that they can avoid undesirable unintended outcomes.

One particularly interesting chapter in the book is the one on fasting. Fasting is an utterly fascinating topic, because it is rife with unintended consequences, some desirable and others not. For example, I have heard it on good authority that when Sumo wrestlers want to gain weight before the competition, they start skipping breakfast. As the explanation goes, the body interprets enforced fasting as a threat of starvation, so it engages various mechanisms to zealously store every calorie consumed. After a few weeks, you walk on the Sumo ring as a kind of a man-mountain. Unless the other guy skipped his own breakfasts, he is toast.


The way my metabolism works, I am not particularly hungry in the mornings. But under the influence of the Sumo story for years I dutifully ate my bowl of cereal for breakfast. The problem is, eating cereal only made me hungrier, so I immediately wanted to eat another bowl. By lunch time I was hungry again, and of course dinner time is when I want to eat a gourmet meal washed down with a couple of glasses of wine (I am kind of partial to good food and wine).

Since I switched to my so-called paleo diet I use a completely different approach. I don’t eat breakfast at all. I start my day with a couple of cups of black coffee (no cream, no sugar). I actually didn’t use to drink coffee before, but I found that the strong taste of coffee, somehow, is enough to satisfy/sublimate any residual need for nutrients. Then I switch to tea (black in the morning, green in the afternoon; again, no milk, no sugar).

Once a week I also skip lunch, and I feel great. My body burns fat, my energy is high, my mind is sharp. Hunger is in the background, but it helps to focus on work. I would do it every day; unfortunately, I found that my stomach can’t handle it if I do it more frequently than once a week. So on other days I eat a salad, which makes my stomach think that it is doing something useful (actually, my body spends more energy digesting the vegetables than it gets from the meal calorie-wise – but let’s not forget the vitamins and micro-nutrients). In the evening I eat as much food as I want (but subject to excluding cereals, legumes, and dairy). But eating fatty foods, meat, fish, and vegetables is quite filling, so I actually end up eating less than before, even though I am not restricting my intake in any way.

By the way, one mildly critical comment I have about Perfect Health Diet is that the Jaminets devote too much space (not a whole lot, but too much, still) to counting calories. Most people, I believe, don’t need to count calories if they eat the right foods and avoid the poisonous ones. Their bodies will tell them when to stop eating.

Now what I have described works for me and I don’t want to push it on anybody else. Not everybody will enjoy “intermittent fasting” (intermittent because it is less than 24 hours, instead of continuing for days) as much as I do. For many people (including myself) intermittent fasting (IM) works as a kind of calorie restriction. I find that, if fasting during the day, I do not need to divert my will power from things that I need it for (on the contrary, short-term fasting seems to sharpen the mind and generate energy – again, this works for me). But there is another reason for all of us to give serious consideration to  IM, and this is something that I first learned from the Jaminets’ book.

Evidence has been accumulating that IM is an excellent strategy for controlling our natural enemies – parasites such as bacteria, protozoa, and viruses. One general principle in theoretical biology states that organisms of different sizes operate on different time scales. While human generations are roughly between two and three decades, a tiny bacterium can divide once per hour (and some even faster). This gives bacteria an unfair advantage in the evolutionary race against humans, but there are costs. In particular, it takes many days to starve a human to death (more than a month, assuming there is enough water). But a bacterium, living on a fast track, starves much faster.

So fasting for 16 or 24 hours is no problem for a person, but it imposes a real hardship on the microorganisms that live within our bodies. Some of them are beneficial and others are harmful. Here’s where the evolutionary theory comes to help. The beneficial or ‘mutualistic’ bacteria (because both bacteria and humans derive mutual benefits from each other) have co-evolved with us for millions of years, and they have learned how to endure periodic bouts of starvation together with their paleolithic human hosts. Harmful bacteria, which tend to be evolutionary recent additions to our microflora, are hit really badly by periods of starvation.

But fasting is good not only because it starves our natural enemies. It also induces ‘autophagy.’ Autophagy (literally, ‘self-eating’) is a natural process used by our bodies to destroy unneeded parts within cells, such as damaged proteins and organelles. Autophagy can also target such pathogens living inside our cells as viruses and protozoa. For example, malaria tends to go into remission in starving people (the malaria parasite is a protozoan).



When things are good and food is plentiful, our bodies tend to take the lazy path and just coast along. But if food becomes scarce, the body thinks, aha!, there are a lot of unneeded things – all that accumulated junk of broken parts – that can be utilized as food. So the cell machinery goes into an overdrive digesting all those things – and the pathogens also get the axe. Which is definitely a good thing. In other words, by starving ourselves we can not only starve the enemy, but also kick into an overdrive the machinery that grinds it up. Altogether a good thing.

It is quite possible that intermittent fasting is as good, or perhaps even better than calorie restriction in improving health and longevity. It is certainly a much more enjoyable way of life. Hey, as long as I get my steak and salad, and a bottle of Burgundy at dinner time, I can fast the rest of the time, no problem! Talk about having your cake and eating it, too.

Notify of
Most Voted
Newest Oldest
Inline Feedbacks
View all comments
Martin Hewson

Have you ever experimented with sous vide cooking? I think it is the most important scientific and technical advance in cooking in a long time.
Here’s a mathematician who calculated very useful tables for sous vide cooking times:

Peter Turchin

Never tried it – actually I had to Google the term. I do like using a crockpot which is probably a good approximation of sous vide.

Martin Hewson

Crockpots are fine but they lack the precision temperature control that’s key to sous vide. They cannot cook meat or fish to rare or medium rare.
The best guide o sous vide I have seen is


Neat Post. Agree that tea, coffee, and… dark chocolate… seem to be good / de facto appetite suppressants. Though that latter has calories that the first two (as you’ve noted) can be consumed without. All of them, for sure, are better than the alleged appetite effects that some people ascribe to cigarettes. Thanks.

Peter Turchin

In addition, according to randomized trial studies, coffee and dark chocolate have a positive effect on various health indicators.

Ross David H

Having just finished Nassim Taleb’s “Antifragility”, I have to point out that he also advocates intermittent fasting. He uses the Orthodox Christian schedule of fasts, apparently, on the logic that he’s got to use some schedule so why not use one that’s been field-tested for many centuries.

Anyway, his logic is essentially that biological things (including humans) tend to be “antifragile”, that is built to benefit from variability (up to a point), thus a thoroughly repeatable schedule of eating is unlikely to be good for us (since the vast majority of human evolution was not under such circumstances). Your post here gives some interesting reasons why this might be so.

I don’t know if you’ve read anything by Taleb, by the way, I don’t recall you mentioning him in previous posts. I’d be curious to hear your opinion someday.

Peter Turchin

I read his Black Swan. Nothing to comment really – I enjoyed most of it (I think it’s a bit long), but part of his message is something that I did my dissertation on (so wasn’t new to me) and the rest I consider an exaggeration. I certainly disagree with him that social dynamics is merely a combination of accidents. I’ll have to write a blog about it at some point…


Interesting post. My personal experience accords well with your experience. I am able to eat just 2 meals per day within a 17-18 hour window and not feel at all hungry. Moreover my appetite is slowly adjusting so that some days I spontaneously eat less than on others. As well my total energy intake has been slowly falling ( I did a careful 58 month trial) and is now lower than the low point in the trial (at which point I did not feel at my best). Where did the extra calories go previously? It is also heartening to hear positive results from someone who is not obviously desperate (as many seem on health blogs) and is used to critical analysis. Why I have good results with somewhat contrarian habits is an ongoing fascination.

Peter Turchin

I agree that the important point is to experiment and keep careful track of results. One problem I have is that I’d like to keep track of how my blood chemistry reacts to different regimes, but the local QuestDiagnostic refuses to run a blood test for me without a doctor’s approval. How did you solve this problem?


I did not find blood chemistry data useful (not sensitive enough) although my total cholesterol did rise to alarming levels and then reverted to slightly above normal over a span of 2 years. As I am old and worn but not broken I can detect changes (ie do experiments) in aging bio-markers in response to lifestyle changes eg dry eyes, night vision, polyurea, hair growth etc but mainly progress of periodontal gum disease (an interesting chronic microbial infection) , which was the motivation for experimenting in the first place. So I have relied on physical symptoms as proxies for bacterial load, immune system activity etc. I do not take my explanations to be more than placeholders but I believe the observations are useful.

Peter Turchin

The nice feature of blood chemistry is that it is objective. You can fool yourself through self-observation (placebo effect). On the other hand, improved periodontal condition is a pretty objective indicator. In fact, several other people reported a dramatic improvement of their teeth health after going on the paleo diet.

green bean

I enjoy what you guys tend to be up too. This kind of clever work and reporting!
Keep up the awesome works guys I’ve included you guys to my blogroll.

  1. Home
  2. /
  3. Cliodynamica
  4. /
  5. Regular Posts
  6. /
  7. Starving the Enemy

© Peter Turchin 2023 All rights reserved

Privacy Policy