Friday, September 18, 2009

Diet As Alchemy

The Surgeon General's Office instructs us that "Overweight and obesity result from excess calorie consumption and/or inadequate physical activity." Oh. Well, case closed then. Never mind that most studies suggest that many who are overweight eat fewer calories than those who are lean, and may be as active. What does reality count in the face of authoritative pronouncements? There would hardly be any religions at all, if evidence mattered. And even less politics. Nothing is so powerful as an idea whose time came thirty years ago and is now thoroughly entrenched. Never mind that in the past thirty years overweight and obesity have nearly tripled.

How can the new standard paradigm, of eat less and burn more, be wrong? Never mind what kind of low fat and what kind of high carbs they tell us to eat -- is the theory behind it valid? Because if it's not, the implication is that we might, somehow, eat an unlimited amount of calories and not gain weight. Calories have to go somewhere. It's physics, the conservation of matter/energy. Either exercise it away or store it as fat. Right? It makes sense.

If triglyceride fat, blubber, can only be formed in the presence of glycerol, what happens to excess calories without glycerol? Well, after general vitality is seen to, and the immune system, and recovery and repair from physical activity -- you know, the reason we eat -- the surplus, since it doesn't go to matter, must go to energy. Heat. That's science.

The simplistic thermodynamic analogy is not valid. True, calories must go either to matter or energy. But a calorie is not a calorie. The caloric value of food is identified by actually burning that food in a crucible in a laboratory. The heat generated is measured, and that's how many calories the food has. Never mind that we cannot digest fiber. That's confounding in only an incidental way. The point is that metabolism is not a crucible, for all that we make heat. It's not a simple energy in-out equation. There are various pathways that lead to multiple outcomes dependent on a number of variables. Well that didn't say a lot, and is quite obvious.

Calories are not about heat. Calorie is another of those misleading-therefore-useless words. What calories are actually about are raw materials, out of which possibilities are made. Thinking in terms of calories is like thinking in terms of carbon -- coal is the same thing as diamonds. Well, yes. And no.

Calories are not just a sort of element, that might happen to manifest as certain allotropes -- incidental forms -- like fats or carbs, as carbon has graphite or diamond, which are both pure elemental carbon. Protein, carbs and fat differ in their fundamental, their elemental nature, and that they burn as calories is as meaningful as the fact that they are made out of matter. Meaningful only because reality is what it is. Protein is as different from carbs as nitrogen is different from, well, carbon. Of course they do not behave the same in the body -- not even as calories.

Absent glycerol, then, triglycerides are not made. Fat would be present in the blood as free fatty acids. Maybe in the liver, maybe in cells, muscle or adipose, but not bundled up for storage. That's not such a good thing. We may end up looking sort of skeletal, all hollow-eyed and sunken-cheeked. Heroin chic. It's a look. Like the burlap-bag-full-of-yogurt look is a look. Somewhere between these two looks is a healthy compromise. But even given an excess of calories, there would be no overweight. I expect you could eat until you just got too hot. Maybe you'd fall into a fevor coma. Maybe you'd spontaneously combust. It's science.

I pulled a muscle in my back tonight. I don't know how. Running? Is that possible? It's the same place as last time, so it's a re-injury. Still. Running. Maybe doing fancy situps. And I have no one to give me a backrub. Is that fair? You know how good I am. Why can't I just be loved? But she has to be hot.


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