tmoody@sjuvax.UUCP (T. Moody) (10/21/85)
In article <528@cadre.ARPA> geb@cadre.ARPA (Gordon E. Banks) writes: >Everyone's metabolism is "trained" to burn fat. If the caloric intake in the >diet is less than the energy expenditure, fat is always burned. >If the intake is in excess it is laid down. One's metabolic >rate can be raised, for example by taking exogenous thyroid >hormone, but this can be quite dangerous. No crackpot diet >is ever going to repeal the law of conservation of energy. >It is probably some variation on the ketotic diet, I would guess. A few years ago, there was an article in _Science_ (and, later, in _Science_83_, or thereabouts) on "setpoint theory". The basic idea is this: if you take a group of chronically overweight individuals and diet them down to a "normal" weight, they will very likely gain that weight back, even though their dietary and exercise habits are kept at the same level as the control group -- people without a weight problem. They will gain weight until they reach the point where they stabilize; they will not gain more. This is their "setpoint." According to this dismal set of studies, each of us has a setpoint that determines the percentage of body fat that our body "wants." The body will adjust its metabolism to get and keep weight at that setpoint. Thus, the "calories in/calories out" formula is rendered less useful (even though it remains true, strictly speaking). Setpoint theory is consistent with a number of observations which we all have made: even when we don't watch what we eat, we don't keep gaining weight, but level off at some (fat) point; some people really do eat more than us, without gaining any weight. About ninety-five percent of all diets are failures, where a "failure" means that the person can't keep the weight off for a year. This is because diets do nothing to alter the setpoint. As I recall, there are only three things that do lower the setpoint: cigarette smoking, amphetamines, and exercise. The dangers of the first two methods appear to be greater than the dangers of being overweight. Exercise works, but more is required than the 3 times/week aerobic minimum. Six vigorous exercise periods per week, as I recall, was the recommended dose. The setpoint will drop, but it will return to its former level or higher if the regimen is discontinued. Todd Moody | {allegra|astrovax|bpa|burdvax}!sjuvax!tmoody Philosophy Department | St. Joseph's U. | "I couldn't fail to Philadelphia, PA 19131 | disagree with you less."