We have identified an eating disorder in 13% of women hospitalized on a medical ward for various reasons. These as well as obese patients undergo wide fluctuations of weight sometimes exceeding 30% of their present weight. Surprisingly, even in the absence of eating disorders, the changes in weight during adulthood are marked (22% of present body weight). Weight history should be included systematically in the medical history, since it can underscore concern over weight or even an unrecognized eating disorder.