Thursday, December 04, 2008

Bury Me Tenderly

It is only a hypothesis, Taubes says repeatedly, and it needs to be confirmed by empirical studies: the idea that what's behind diabetes, obesity, and most cardiac disease and cancer is the huge amounts of sugar, corn syrup, white flour and potatoes that have swamped the human diet, throwing the metabolic processes slightly out of kilter. But it's a hypothesis that explains the epidemiology of all those new, chronic diseases of Western Civilization. I am only suspicious of it now, because I so much want it to be true.

Most of my life I've been forty to sixty pounds overweight, and I've been told all my life that my inability to control my diet puts me in line for all these diseases, and that if only my will were not defective I would be healthy and lean. The metabolic hypothesis turns all this upside down. What if, as Taubes puts it, we don't get fat because we overeat? What if we overeat because we're getting fat?

At first that sounds like pure nonsense. But if the fat tissue is getting first dibs on the fuel coming in, and releases it only reluctantly, the body will respond by getting hungrier, and by decreasing its energy expenditure. We'll be hungry and reluctant to move. Which is precisely what is seen in the couch potatoes we love to ridicule. The correlation between overeating, sedentary habits, and obesity is obvious: but corellation is not causation. And the spectacular failure of programs of calorie-restricted diets and exercise to change the condition, despite huge and aggressive public health campaigns, and the fact that such basic vices as Vanity, Envy, Pride, and Lust can easily be rallied to their support, leaving only poor lightweights like Greed and Sloth to try to hold the line, should make us wonder if, after all, we've really got it right.

A theme I return to again and again is my skepticism about how much of what we do is really under the control of the storytelling part of the brain. A lot of that skepticism was born of my experiences in trying, and failing, to eat as people told me I should. My commitment to a diet would be as complete as I can imagine, my intention focused, my resolution of a sort that I've brought fruitfully to bear on all kinds of other things -- and within a few days I would have caved in completely. Perhaps I am a deeply defective person. I have many reasons to think so. But perhaps I was engaged in an endeavor that made no sense.

Picture a world in which all the medical authorities told us that our health problems and our unattractiveness were the result of taking in and storing too much oxygen. (Oxygen, after all, is a highly toxic substance: look what it does to iron!) If we would only breathe more moderately, then we would be healthy and attractive. You can picture what would ensue. All kinds of people would offer ingenious methods of breath-control. Learned authorities would get up in front of television cameras and tell us that of course the breath is under voluntary control, and it only wants discipline. People would invest enormous amounts of emotional and financial capital in controlling their breath. We would see psychologists investigating our pathological emotional commitment to overbreathing. And the sum total of oxygen consumed would not change a bit.

Because, despite the fact that yes, you can in the short term decide whether or not to breathe, in the long term you cannot. The body simply doesn't trust the conscious mind to run that process. If you don't do what it wants, it will take over and override the conscious mind entirely. The hypothalamus was here first. What it says goes. The cerebral cortex can sit lordly on its throne and issue orders all day, and as long as its orders don't contradict the hypothalamus its delusion of autocracy can remain intact. But put them in direct conflict, and you'll soon find out who's boss.

The only time I've lost weight easily -- almost spookily easily -- was on a version of the Atkins diet, a few years ago. Without any attempt to cut calories, without any portion control, without any attention to whether I bolted my food or ate slowly, and without any hunger, I'd lose a couple pounds a week. The rate at which I lost weight, in fact, concerned me: I'd been told that weight loss that rapid was unhealthy, and I tried to slow it up a bit. What concerned me even more was that I was eating a diet which medical authorities told me was horribly unhealthy. I assumed, at the time, that they had an empirical basis for this. I've learned since never to assume that about nutrition. For some reason nutritionists feel that they are exempt from empirical demonstration. After seeing authority after authority solemnly state that high-protein diets caused kidney damage, I decided to go look for myself and see what the studies were that proved this. It turned out that if you force-feed rabbits huge amounts of animal proteins they develop kidney problems. This was the only empirical basis for the supposed toxicity of high protein diets. The rest was all speculation, speculation which accounted rather badly for the good health and longevity of human populations which traditionally eat almost nothing but meat and fat. Why the Inuit and Masai weren't all on dialysis by age thirty (not to mention, why they weren't all dying of scurvy after three months of their animal-only diets) was left unexplained. furthermore -- and this is typical of nutritional "science," at least until recently -- no one even seemed to feel that it needed any explaining.

So. I had been planning to wait until after Christmas to undertake my new eating program. But I'm so excited about it that I think I'm going to do it now. It's not proven yet, but the weight of the evidence seems to me to indicate pretty clearly that refined carbohydrates are, at least for some people, metabolic poison. And Taubes' review of the evidence has convinced me that dangers of high protein & fat diets is purely speculative. (And the fact that it is still speculative, after so long a time as a ruling ideology of diet, is itself a sort of negative evidence. There's been plenty of time and opportunity to demonstrate this empirically. Why has no one ever managed to do it?) Likewise, I no longer believe that the supposed nutritional indispensability of carbohydrates has been demonstrated, or even proven to be likely.

So I'm off to undertake a fad diet. Bury my atherosclerotic body tenderly, next year! It's all Taubes' fault.

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