Anorexia nervosa is an eating disorder in which a person refuses to stay at even the minimum body weight considered normal for their age and height. Persons with this disorder may have an intense fear of weight gain and a distorted body image. Inadequate eating or excessive exercising results in severe weight loss.

See also:

• Bulimia
• Intentional weight loss

The exact cause of anorexia nervosa is not known, but social attitudes towards body appearance, as well as family factors, are believed to play a role.

Anorexia nervosa usually occurs in adolescence or young adulthood. It is more common in females. The eating disorder is seen mainly in Caucasian women who are high academic achievers and have a goal-oriented family or personality.

Some experts have suggested that conflicts within a family may contribute to this eating disorder. It is thought that anorexia is a way for a child to draw attention away from marital problems, for example, and bring the family back together.

Other psychologists have suggested that anorexia may be an attempt by young women to gain control and separate from their mothers.

Most individuals with anorexia nervosa refuse to recognize (deny) that they have an eating disorder.

Symptoms may include:

• Weight loss of 15% or greater below the expected weight
• Inappropriate use of laxatives, enemas, or diuretics (water pills) in an effort to lose weight
• Self-imposed food intake restrictions, often hidden
• No menstruation
• Skeletal muscle atrophy
• Loss of fatty tissue
• Low blood pressure
• Dental cavities due to self-induced vomiting
• Blotchy or yellow skin
• Depression

A diagnosis of anorexia nervosa is not made until other causes of weight loss are ruled out. The health care provider will determine if endocrine, metabolic, digestive, and central nervous system abnormalities can explain the weight loss. (For example, extreme weight loss could be due to celiac disease, inflammatory bowel disease, Addison's disease, and many other possible conditions.)

Tests will be done to help determine the cause of weight loss or to determine what damage the weight loss has caused cause. They may include:

• CHEM-20
• Urinalysis
• Thyroid function tests
• ECG
• LH response to GnRH