Applied physiology: the control of weight

Abstract

Our understanding of the mechanisms involved in body-weight regulation has increased enormously over the last decade. Unfortunately, the same time period has seen a doubling in prevalence of childhood and adult obesity, the health consequences of which are enormous. While the cause for this increase undoubtedly lies in changes to our social environment, genetic factors strongly influence the response to these environmental changes.We review the current understanding of the systems controlling energy homeostasis including: the role of leptin and insulin as adiposity signals; neuropeptide Y andα -melanocyte stimulating hormone as central mediators of the effects of these signals; and cholecystokinin as a satiety factor regulating meal size. Our hope is that our improving knowledge of the pathways regulating homeostasis and the dysregulation that occurs in obesity will lead to new and more effective treatments. The principal challenge, however, lies in changing the way we live so that obesity is not inevitable in a large proportion of the population.