[New knowledge about obesity--news for obese patients?].

This review explains and surveys very recent findings and experimental results concerning molecular pathology and genetics of overweight and obesity and also evaluates their relevance for the actual treatment of obesity at present. Most of these studies were done on inbred obese mice or rats and it is yet unknown to what extent the results do apply to human overweight. Nevertheless these studies led to the discovery of a new hormone--OB-protein or leptin--produced by adipocytes of animals. It does not only increase satiety by influencing feeding centers and decrease body weight but it also interferes with several peripheral metabolic functions. Mutations of leptin expression or expression of leptin receptors as observed in animals are, however, very rare in humans. In obese individuals (and animals) there is a yet unexplained resistance to the effects of leptin which interferes with successful therapeutic use of leptin in human obesity. Various other recently discovered transmitters modifying feeding habits may, however, become targets of future drugs making dietary weight loss and its maintenance more acceptable and successful. At present obese people and patients have to rely, however, on traditional methods of weight loss though these are known to yield poor results over prolonged periods of time. Orlistat, a recently introduced drug results in malabsorption of fat from the gut by inhibiting lipases. Though it is not based on recent insights to regulation of body weight it is promising primarily for educating patients to reduce their nutritional fat intake.