Central nervous system control of food intake and body weight

The capacity to adjust food intake in response to changing energy requirements is essential for survival. Recent progress has provided an insight into the molecular, cellular and behavioural mechanisms that link changes of body fat stores to adaptive adjustments of feeding behaviour. The physiological importance of this homeostatic control system is highlighted by the severe obesity that results from dysfunction of any of several of its key components. This new information provides a biological context within which to consider the global obesity epidemic and identifies numerous potential avenues for therapeutic intervention and future research. The roots of obesity The widespread epidemic of obesity has focused attention on the nature of the central nervous system processes that control food intake and body weight. In response to reduced body fat stores, both the motivation to find food and the size of a meal (via satiety perception) increase until energy stores are replenished, and mutations influencing this neuronal process can cause severe obesity in both animal models and humans. In theory, drugs that target neuronal receptors for leptin and other relevant ligands have potential as antiobesity agents, but hoped-for therapeutic breakthroughs have yet to emerge. Morton et al . review the latest research in this area, highlighting the subtle differences between normal and abnormal energy homeostasis.