Anorexia nervosa

Alternative Names

Eating disorder – anorexia

Definition of Anorexia nervosa

Anorexia nervosa is an eating disorder that involves an inability to stay at the minimum body weight considered healthy for the person’s age and height.

Causes, incidence, and risk factors

The exact causes of anorexia nervosa are unknown. Many factors probably are involved. Genetics and hormones may play a role. Social attitudes that promote unrealistically thin body types may also contribute.


To be diagnosed with anorexia, a person must:

Signs and tests

Other causes of weight loss or muscle wasting must be ruled out with medical testing. Examples of other conditions that can cause these symptoms include:


The biggest challenge in treating anorexia nervosa is having the person recognize that they have an illness. Most persons with anorexia nervosa deny that they have an eating disorder. Individuals often enter treatment only once their condition is fairly advanced.

Expectations (prognosis)

Anorexia nervosa is a serious and potentially deadly medical condition. By some estimates, it leads to death in 10% of cases. Experienced treatment programs have a good success rate in restoring normal weight, but it is common for the disease to return.


David B. Merrill, MD, Assistant Clinical Professor of Psychiatry, Department of Psychiatry, Columbia University Medical Center, New York, NY. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 2/7/2010

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ADAM Medical Encyclopedia

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