Set-Point Theory

Set-Point Theory

the center of Health Promotion &Wellness at MIT Medical

• According to the set-point theory, there is a control system built into every person dictating how

much fat he or she should carry – a kind of thermostat for body fat. Some individuals have a

high setting, others have a low one. According to this theory, body fat percentage and body

weight are matters of internal controls that are set differently in different people.

• The set-point theory was originally developed in 1982 by Bennett and Gurin to explain why

repeated dieting is unsuccessful in producing long-term change in body weight or shape. Going

on a weight-loss diet is an attempt to overpower the set point, and the set point is a seemingly

tireless opponent to the dieter.

• The ideal approach to weight control would be a safe method that lowers or raises the set point

rather than simply resisting it. So far no one knows for sure how to change the set point, but

some theories exist. Of these, regular exercise is the most promising: a sustained increase in

physical activity seems to lower the setting (Wilmore et al. 1999).

• According to the set-point theory, the set point itself keeps weight fairly constant, presumably

because it has more accurate information about the body’s fat stores than the conscious mind can

obtain. At the same time, this system pressures the conscious mind to change behavior,

producing feelings of hunger or satiety. Studies show that a person’s weight at the set point is

optimal for efficient activity and a stable, optimistic mood. When the set point is driven too low,

depression and lethargy may set in as a way of slowing the person down and reducing the

number of calories expended.

• 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.

• Dieting research demonstrates that the body has more than one way to defend its fat stores.

Long-term caloric deprivation, in a way that is not clear, acts as a signal for the body to turn

down its metabolic rate. Calories are burned more slowly, so that even a meager diet almost

suffices to maintain weight. The body reacts to stringent dieting as thought famine has set in.

Within a day or two after semi-starvation begins, the metabolic machinery shifts to a cautious

regimen designed to conserve the calories it already has on board. Because of this innate

biological response, dieting becomes progressively less effective, and (as generations of dieters

have observed) a plateau is reached at which further weight loss seems all but impossible. 

Adapted from Integrative Group Treatment for Bulimia Nervosa by Helen Riess, M.D. and Mary Dockray-Miller

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