Overview of the physiological control of eating.

In this chapter we discuss the physiology of eating, with a particular focus on its relevance to the present obesity epidemic. The physiology of eating comprises the functional organization of eating behavior, the types of exteroceptive and interoceptive information that affect eating, the neural and endocrine sensory mechanisms relaying this information to the central nervous system (CNS), and the CNS neural networks that process and integrate this and other information to control eating (fig. 1). We emphasize the role of eating in the regulation of body weight. These topics have taken on new importance with the obesity epidemic. It is well recognized that overeating together with reduced exercise are the proximal causes of obesity. Therefore, better understanding of the physiology of eating and its role in body weight regulation, or dysregulation, should lead to new and hopefully more effective approaches for the therapeutic control of eating in obese persons or persons at special risk for obesity and obesity-related diseases.