Weight Set Point
According to the weight set point theory, there is a control system built into every person which dictates how much fat they should carry...much like a thermostat for adipose fat. Originally developed in 1982 by Bennit and Gurin to explain why repeated dieting was so unsuccessful. Going on restricted diet to alter the bodies weight set point has been shown to be a tireless effort.
The key would be to alter the set point in a safe and effective manner, although no known method has been proven to do this. Theories exist but the overall mechanisms require more research before common advise can be given out.
"The set point, it would appear, is very good at supervising fat storage, but it cannot tell the difference between dieting and starvation. The dieter who begins a diet with a high set point experiences constant hunger, presumably as part of her body’s attempt to restore the status quo. Even dedicated dieters often find that they cannot lose as much weight as they would like. After an initial, relatively quick loss, dieters often become stuck at a plateau and then lose weight at a much slower rate, although they remain as hungry as ever. " - Integrative Group Treatment for Bulimia Nervosa by Helen Riess, M.D. and Mary Dockray-Miller
The following excerpts are taken from an interview with Rudolph Leibel http://www.scientificamerican.
Rudolph Leibel: "The reason for believing that there is a set point to human body weight is based on some animal experiments, some epidemiology and some clinical medical observations. The animal observations were made in the 1940s and 1950s by an experimental physiologist who manipulated the brains of rodents and some higher mammals with electrolytic and knife lesions, showing that there are areas of the brain that have very powerful effects on appetite and weight regulation in animals."
"In fact, when you look at the numbers-and they're hard to get, because for a number of reasons, many of the commercial enterprises don't necessarily want to publicize this-the recidivism rate to obesity following what would be considered a successful weight reduction is probably over 95 percent."
"what does characterize the vast majority of humans is that they are very resistant to the maintenance of body weight below whatever "normal" for them is. "
"You can account for virtually all the energy expenditure in a human by knowing their lean body mass and their physical activity. So we found that a gain in body weight causes the individual to spend more energy than you would predict based on their new lean body mass. In other words, they actually fall above the regression line that they were on at usual body weight. The amount of this increase is something like 15 percent above what you would predict. You may say, "well, 15 percent, that's not very much." But 15 percent is a lot when you consider that one-tenth of one percent is the estimated degree of balance over a long period of time. What this means is that unless this individual is able to overeat by 15 percent, or to reduce physical activity by 15 percent, they are going to fall back to their starting body weight. In fact, in all instances in which we have performed this experiment, which must number well over 40 now, the individuals fall back to their starting weight. Obese people don't hang up, lean people don't hang up there; all of them come back."
"Their is no difference in the energy requirements of an obese person and a lean person."
"One interesting way of looking at this is to ask: what is it that a formerly obese person has-or that a normal person has when they are down in weight-that is different? Well, we know now that their energy expenditure is lower than you would expect. And we know that they are very uncomfortable. People complain that they feel cold, they feel hungry-not normal. Invariably, what happens is that both obese and lean people bounce back up to their starting body weight. We know now what the mechanism is, at least from an energy perspective: they are spending 15 percent less energy than they need, they cannot comfortably reduce their food intake indefinitely by 15 percent, so what happens is that they eat at their normal level, it is 15 percent more than their body needs to maintain weight, and they bounce back up again. "
According to Seth Roberts Food-Calorie association can raise or lower the weight set point as well.
"The theory takes a familiar idea -- body fat is regulated by a system with a set point – and adds two rules about how the set point changes. One rule is that calorie-associated flavors raise the set point – the stronger the association, the greater the increase. The other rule is that these increases are superimposed on a steady decline – the greater the set point, the faster the decline. A steady state is reached when the rate of flavor-generated increases equals the rate of decline." - What makes food fattening? (February 2005 version)
Now this is just a theory not necessarily the be all end all. However, it does offer a new perspective which is much needed with our "war" on obesity.