Understanding the physiology of obesity: review of recent developments in obesity research.

Knowledge of the genetic and regulatory factors that influence energy homeostasis is advancing rapidly. There is increased understanding of the molecular signals that reach the brain with information regarding the current state of energy balance, how those signals are detected by the brain, and key neuronal systems important in translating the information into efferent responses. The identification of molecules that control food intake has generated new targets for drug development in the treatment of obesity. In view of the complexities of the energy control system, therapeutic strategies that target only one site are likely to be less effective than those targeting two or more sites.