Comment les régimes amaigrissants font grossir : d'une perspective d'autorégulation de la composition corporelle

'Dieting Makes You Fat' - the title of a book published in 1983 - embodies the notion that dieting to control body weight, with consequential weight cycling, predisposes the individual to acquire even more body fat. While this notion is controversial, its debate underscores the large gap, which exists in our understanding of basic physiological laws, which govern the regulation of human body composition. In addressing the plausibility and mechanistic basis by which dieting may predispose to increased fatness, this paper integrates the results derived from re-analysis of classic longitudinal studies of human starvation and refeeding. These suggest that feedback signals from both fat and lean tissues contribute to recovering body weight through effects on energy intake and thermogenesis, and that a faster rate of fat recovery relative to lean tissue recovery is a central outcome of body composition autoregulation that drives fat overshooting. A main implication of these findings is that the risk of becoming fatter in response to dieting is greater in lean than in obese individuals.