Anorexia nervosa is characterized by low body weight, an intense fear of gaining weight, distorted body image, and an extreme focus on shape, weight, and size. It carries the highest death rate of any psychiatric illness, and its complications are a direct consequence of starvation and weight loss. Anorexia recovery is crucial to survival.

While anorexia nervosa is defined by low body weight, it is divided into two types: restricting and binge-purge based on the mechanism used to achieve low body weight. There are many common physical side effects to both types with a few unique consequences in the binge-purge subtype.