Abstract
The need to understand the regulation of appetite and energy balance has never been greater. The emergence of obesity as a global public health problem has imparted impetus to efforts directed at characterizing the complex neuroendocrine interactions that govern feeding. Similarly, eating disorders are responsible for very significant morbidity, mortality, and socioeconomic dysfunction. A recent review of outcomes in anorexia nervosa (AN) painted a gloomy picture, reporting a crude mortality rate of 5% and a recovery rate of less than 50% (1), figures that have changed little over the course of the last century. More effective therapeutic approaches are needed, and it is in this context that work to define better the pathogenesis of AN has been making progress. With some timely data on peptide YY (PYY) in AN, Misra et al. (2) supplement our existing knowledge of the changes in the gut hormone milieu that accompany changes in body weight.