Saturday, September 26, 2009

You gonna finish that?

It's time at last to look at hunger.

Carbs are like a certain ethnic food. An hour later and you're hungry. I always believe stereotypes, because they are always true. Ask me how big my feet are. Obviously, too many easily digested carbs instigates a massive insulin response, which steals too much bloodsugar and stores it away, eventually as fat. The result, low bloodsugar, is a hunger cue. Whether the cue originates from some monitoring mechanism in the brain, or emanates from energy-deprived cells, is speculation, and fundamentally irrelevant. But we'd like to know.

Because, like, it's so odd that a calorie-restricted diet that is low-carb but includes lots of fat is not accompanied by hunger. This is the overwhelmingly reported experience of dieters, even under clinical supervision. Whether it's the absence of carbs that eliminates hunger, or the surfeit of fat, is, again, speculative. The phenomenon itself is what's important in practical terms.

It's both, of course. Refined carbs make you hungry. Ample dietary fat satiates you. Given two calorie-restricted diets with the same number of calories, the high carb diet will make you lethargic and fatigued and irritable, while the fat-rich one will leave you with less blubber and more energy. The cellular starvation created by too much insulin, which overfeeds fat cells, is avoided in the absence of insulin and the presence of FFAs in the bloodstream.

Indeed, starvation and fasting are both notable for the absence of hunger. Whereas, feed someone who's fasting a few hundred calories of carbs, and they become ravenous. I can attest to the truth of this lack of hunger, having fasted, years ago, for ten days. Water only. No hunger. Just the feeling that I'd neglected to do something.

So, hunger is decoupled from calorie intake. Hunger is dependent on insulin and the type of macronutrients ingested. Hunger is not about a taste, not about a fullness in the belly, not about calories per se in the bloodstream. It's about insulin acting on bloodsugar. So the data suggest.

If thermodynamics is what it's claimed to be, then leanness and obesity is a straightforward proposition. If calorie intake goes up and energy output also goes up -- as either heat or activity -- then there is no significant weight change. Likewise, if energy-in is decreased and so is output -- reduced bodyheat or activity -- same result, of no weight change. If it's more energy in and less energy out -- due to either reduced heat or increased storage -- well, obesity. And then there's less in, more out. Thinness.

That's the theory. Thermodynamics.

It's not my problem, that this theory does not work for fat people. I'm not fat, and only a few of the fat people I know will change their behavior because of what I say. But the reality is that, for healthy people, by which I mean people with a not-hysterical insulin response, they can eat crap and look good. But those who tend to obesity, not so much. They store it. Likewise if their calorie intake goes down, and their activity level goes up, or down. They store it. They will always store it, regardless of thermodynamics. Because insulin trumps physics. Biology then is a sort of metaphysics. Kidding. Not really. Only sort of. But only sort of.

Mixed in with all this mystery, this alchemy, is hunger. Just as glycerol transforms free fatty acids into triglycerides, insulin transforms carbs into hunger. Dietary fat plays at most only a minor role in any of this. How odd.

Obese people, then, have two problems relevant to this discussion. Insulin hysteria is one. The other is that they release free fatty acids from adipose cells more slowly than lean people do. They hoard it. So there's less energy available between meals. Cells are starved. Hunger. Because the last meal's glucose was hoarded away by insulin. Double hoarding.

So many complex ideas, expressed so clearly and simply. I'm brilliant. And I'm still waiting for that dollar you promised to send me. What, I'm not worth a dollar to you? That hurts my feelings. How would you like it if this was my last post?


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