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Overview of Eating Disorders


Evelyn Attia

, MD, Columbia University Medical Center;

B. Timothy Walsh

, MD, College of Physicians and Surgeons, Columbia University

Reviewed/Revised Jul 2022 | Modified Dec 2022

Eating disorders involve a disturbance of eating or of behavior related to eating, typically including

  • Changes in what or how much people eat

  • Measures people take to prevent food from being absorbed (for example, making themselves vomit or taking a laxative)

For unusual eating behavior to be considered a disorder, the behavior must continue for a period of time and cause significant harm to the person's physical health and/or ability to function at school or work or negatively affect the person's interactions with other people.

Eating disorders include

Anorexia nervosa is characterized by a relentless pursuit of thinness, a distorted body image, an extreme fear of obesity, and restriction of food consumption, leading to a significantly low body weight. People with anorexia nervosa restrict their intake of food, but they may also binge eat, then compensate by purging (for example, by making themselves vomit or using laxatives). People who have the disorder may restrict their food intake to the point where their health is harmed. Although anorexia means loss of appetite, many people with anorexia nervosa do not lose their appetite until they are very emaciated.

Avoidant/restrictive food intake disorder is characterized by eating very little food and/or avoiding eating certain foods without the concern about body shape or weight that is typical in people with anorexia nervosa or bulimia nervosa. Usually, people with this disorder may lack interest in eating, may be extremely picky about food, and may avoid certain types of food. For example, they may avoid foods that are a certain color, consistency, or odor. Some people are afraid of possible adverse consequences of eating such as choking or vomiting.

Binge eating disorder is characterized by eating unusually large amounts of food—much more than most people would eat in a similar time under similar circumstances. People feel a loss of control during and after binge eating, and are distressed by these episodes. Binge eating is not followed by purging or other attempts to compensate for the excess food eaten.

Bulimia nervosa is characterized by repeated episodes of rapidly eating large amounts of food, followed by attempting to compensate for the excess food consumed. For example, people may make themselves vomit or take laxatives.

Pica is regularly eating things that are not food.

Rumination disorder is characterized by regurgitation of food after eating.

Eating disorders are more common among women, especially younger women, than among men.

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

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