The craziness of calorie restriction dieting

27 Jul

Why is calorie restriction still considered a viable approach to weight loss? Study after study shows that the failure rate of such diets is essentially 100%. A recent Harvard Medical Letter “Healthbeat” ¬†continues to espouse the thesis that the human body is just like an automotive engine, each gram of fuel produces exactly the same caloric effect, with no ability to dispose of excess calories in any other way than to turn them into adipose tissue (fat). Their idea is that if a person will only reduce the caloric value of what they eat by 3500 Kcals, then the body will be obliged to lose one pound of weight. No allowance is made for body metabolism adaptation.

This has got to be wrong. Most (all?) systems in the body have exquisite feedback. An example is the kidneys; they retain or dispose of many things differently, including water, depending upon body needs. Has anyone ever really, scientifically studied whether the GI system absorbs food differently depending on the body’s current needs (i.e., hunger level)? The GI system must have any number of ways of not absorbing that which the body doesn’t need. The alternative, that the system must always, always absorb exactly the same number of calories per gram regardless of hunger level, would run counter to any other body system.

So, then, if your body isn’t just a machine only capable of making fat from every single excess calorie, why do some people have so much adipose tissue (fat)? Studies demonstrate that adipose tissue (fat) grows in the presence of elevated serum insulin and shrinks as insulin decreases. The strange thing is, to paraphrase Gary Taubes, standard medical texts clearly describe the adipose tissue-insulin effect, yet later the same texts attribute obesity ¬†to “overeating”.

For those of us who have given up carbohydrates (well, almost…) the results can be spectacular. Eating lots of eggs, cheese, meat, green veggies (sparingly) is kind of boring, but my oh my, the weight comes off without ever thinking about calorie restriction. Most everybody I know can only eat so much of that stuff before they get really, really full. I can be absolutely, positively full and not want another bite, but if someone offers anything with carbs (bread, cookies, and pies, oh my) suddenly I have room for quite a lot more. Not that I’m hungry, I just crave most anything carb related.