Compare and contrast the two subtypes of anorexia nervosa.

DSM-5 subtypes anorexia nervosa into the restricting type and the binge eating/purging type. Approximately half of individuals with a diagnosis of anorexia belong to either subtype. In the restricting type, low weight is maintained by a rigidly controlled diet and a very low intake of food. In the binge eating/purging type, restraint breaks down regularly and binge eating occurs. Self-induced vomiting, abuse of laxatives, diuretics, and enemas are used to maintain low body weight and to rid the body of calories. In both subtypes, excessive exercise is used to burn off unwanted calories. Although both subtypes are in the same diagnostic category, the distinction between them is important for treatment purposes. There is evidence that the binge-purge subtype is associated with more impulsive behaviours, such as substance abuse, self-mutilation and suicidal ideation. Treatment outcome studies have shown that the binge-purge subtype has a poorer long-term prognosis.