Eating disorders involve serious disturbances in eating behavior, including unhealthy reduction of food intake, severe overeating and/or dangerous methods to prevent weight gain, such as self-induced vomiting. Severe eating disorders may result in serious health consequences including death.

Patients can be diagnosed with an eating disorder at any age, but they most often develop during adolescence and young adulthood. More women than men are diagnosed with eating disorders.

The most common types of eating disorders are anorexia nervosa, bulimia nervosa and binge eating disorder. Other, less common types of eating disorders include pica and rumination disorder.

In addition, some patients may have an eating disorder that does not fit the criteria for any of the recognized eating disorders. In such cases, a diagnosis known as “eating disorder not otherwise specified” (EDNOS) may be made.

The exact cause of eating disorders is not known, but they are believed to result from a combination of genetic, psychological and environmental factors. Most recently, researchers are studying the possibility of biochemical or biological causes for the development of eating disorders. Some patients with eating disorders exhibit imbalances in certain chemicals in the brain that control hunger and appetite.Eating disorders are also believed to be contributed to in part from a media environment that celebrates levels of thinness that may be impossible to maintain. According to a 2005 Youth Risk Behavior Study, 61 percent of adolescent girls were trying to lose weight.

Patients with eating disorders frequently have other types of mental health disorders including depression, anxiety disorders (e.g., obsessive-compulsive disorder) and substance abuse. They often exhibit symptoms including an excessive preoccupation with food, extreme unhappiness or concern about body shape and size, menstrual irregularities, excessive exercise routines and chronic fatigue.

Eating disorders are usually diagnosed after a physical examination, including a complete medical history. The physician may check the patient’s vital signs and perform tests (e.g., blood tests) to rule out medical conditions that may be causing symptoms. The physician will also ask about the patient’s history of dieting and/or eating patterns, as well as assess their attitude toward food and weight gain/loss. Once an eating disorder is diagnosed, a physician may refer the patient to a mental and/or behavioral health specialist (typically a psychiatrist) for further evaluation and treatment.

Due to their complex nature, eating disorders usually require a comprehensive treatment plan including medical care and monitoring of health complications (e.g., malnutrition, obesity), psychotherapy and dietary counseling by a nutritionist.

Receiving support from family members and friends is important because often patients with eating disorders are in denial and resist treatment, believing they do not need help.

The outlook for patients with eating disorders is generally favorable with early treatment.