Regulation of body adiposity and the problem of obesity

The hypothesis that body adiposity is homeostatically regulated is the focus of an intensive research effort, and support for this concept is rapidly growing. While generating optimism about the future of obesity treatment, these advances also bear on our current approach to the obese patient. The observation that body adiposity appears to be subject to regulation in obese as well as lean individuals suggests that common forms of obesity may result from a primary disorder of the weight-regulatory system. As a result, voluntary efforts to lower body adiposity activate compensatory responses that limit weight loss and facilitate weight regain. The use of weight-reduction strategies based on caloric restriction, therefore, effectively pits the will of the obese individual against his or her own intrinsic weight-regulatory system. Until more effective approaches to weight reduction are available, we suggest that clinical intervention should focus on patient education and strategies to limit weight gain or modestly lower weight. Since the combination of a low-fat diet with an exercise program appears to reduce the level at which body weight is regulated without active caloric restriction, this approach may be appropriate for many obese individuals.