Causes

The exact causes of anorexia nervosa are unknown. Many factors probably are involved. Genes and hormones may play a role. Social attitudes promoting very thin body types may also be involved.

Family conflicts are no longer thought to contribute to this or other eating disorders.

Risk factors for anorexia include:

• Trying to be perfect or overly focused on rules
• Being more worried about, or paying more attention to, weight and shape
• Having eating problems during infancy or early childhood
• Certain social or cultural ideas about health and beauty
• Having a negative self-image
• Having an anxiety disorder as a child

Anorexia usually begins during the teen years or young adulthood. It is more common in females, but may also be seen in males. The disorder is seen mainly in white women who are high academic achievers and who have a goal-oriented family or personality.

Symptoms

To be diagnosed with anorexia, a person must:

• Have an intense fear of gaining weight or becoming fat, even when she is underweight
• Refuse to keep weight at what is considered normal for her age and height (15% or more below the normal weight)
• Have a body image that is very distorted, be very focused on body weight or shape, and refuse to admit the seriousness of weight loss
• Have not had a period for three or more cycles (in women)

People with anorexia may severely limit the amount of food they eat, or eat and then make themselves throw up. Other behaviors include:

• Cutting food into small pieces or moving them around the plate instead of eating
• Exercising all the time, even when the weather is bad, they are hurt, or their schedule is busy
• Going to the bathroom right after meals
• Refusing to eat around other people
• Using pills to make themselves urinate (water pills or diuretics), have a bowel movement (enemas and laxatives), or to decrease their appetite (diet pills)

Other symptoms of anorexia may include:

• Blotchy or yellow skin that is dry and covered with fine hair
• Confused or slow thinking, along with poor memory or judgment
• Depression
• Dry mouth
• Extreme sensitivity to cold (wearing several layers of clothing to stay warm)
• Loss of bone strength
• Wasting away of muscle and loss of body fat

Exams 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:

• Addison's disease
• Celiac disease
• Inflammatory bowel disease

Tests should be done to help find the cause of weight loss, or see what damage the weight loss has caused. Many of these tests will be repeated over time to monitor the patient.

These tests may include:

• Albumin
• Bone density test to check for thin bones (osteoporosis)
• CBC
• Electrocardiogram (ECG or EKG)
• Electrolytes
• Kidney function tests
• Liver function tests
• Total protein
• Thyroid function tests
• Urinalysis

Treatment

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

The goals of treatment are to restore normal body weight and eating habits. A weight gain of 1 - 3 pounds per week is considered a safe goal.

A number of different programs have been designed to treat anorexia. Sometimes the person can gain weight by:

• Increasing social activity
• Reducing physical activity
• Using schedules for eating

Many patients start with a short hospital stay and continue to follow-up with a day treatment program.

A longer hospital stay may be needed if:

• The person has lost a lot of weight (being below 70% of their ideal body weight for their age and height). For severe and life-threatening malnutrition, the person may need to be fed through a vein or stomach tube.
• Weight loss continues even with treatment
• Medical complications, such as heart problems, confusion, or low potassium levels develop
• The person has severe depression or thinks about committing suicide

Care providers who are usually involved in these programs include:

• Nurse practitioners
• Physicians
• Nutritionists or dietitians
• Mental health care providers

Treatment is often very difficult, and patients and their families must work hard. Many therapies may be tried until the patient overcomes this disorder.

Patients may drop out of programs if they have unrealistic hopes of being "cured" with therapy alone.

Different kinds of talk therapy are used to treat people with anorexia:

• Individual cognitive behavioral therapy, group therapy, and family therapy have all been successful.
• The goal of therapy is to change a patient's thoughts or behavior to encourage them to eat in a healthier way. This kind of therapy is more useful for treating younger patients who have not had anorexia for a long time.
• If the patient is young, therapy may involve the whole family. The family is seen as a part of the solution, instead of the cause of the eating disorder.
• Support groups may also be a part of treatment. In support groups, patients and families meet and share what they've been through.

Medications such as antidepressants, antipsychotics, and mood stabilizers may help some anorexic patients when given as part of a complete treatment program. Examples include:

• Antidepressants
• Olanzapine (Zyprexa, Zydis)
• Selective serotonin reuptake inhibitors (SSRIs)

These medicines can help treat depression or anxiety.

Although these drugs may help, no medication has been proven to decrease the desire to lose weight.

Support Groups

See: Eating disorders - support group

Outlook (Prognosis)

Anorexia nervosa is a serious condition that can be deadly. By some estimates, it leads to death in 10% of cases. Experienced treatment programs can help people with the condition return to a normal weight, but it is common for the disease to return.

Women who develop this eating disorder at an early age have a better chance of recovering completely. However, most people with anorexia will continue to prefer a lower body weight and be very focused on food and calories.

Weight management may be hard. Long-term treatment may be needed to stay at a healthy weight.

Possible Complications

Complications can be severe. A hospital stay may be needed.

Complications may include:

• Bloating or swelling
• Bone weakening
• Electrolyte imbalance (such as low potassium)
• Dangerous heart rhythms
• Decrease in white blood cells, which leads to increased risk of infection
• Severe dehydration
• Severe malnutrition
• Seizures due to fluid loss from repeated diarrhea or vomiting
• Thyroid gland problems, which can lead to cold intolerance and constipation
• Tooth decay

When to Contact a Medical Professional

Talk to your doctor if a loved one is:

• Too focused on weight
• Over-exercising
• Limiting his or her food intake
• Very underweight

Getting medical help right away can make an eating disorder less severe.

Prevention

In some cases, prevention may not be possible. Encouraging healthy, realistic attitudes toward weight and diet may be helpful. Sometimes, talk therapy can help.

Alternative Names

Eating disorder - anorexia

References

Treasure J, Claudino AM, Zucker N. Eating disorders. Lancet. 2010; 375(7914):583-593.

Attia E, Walsh BT. Behavioral management for anorexia nervosa. N Engl J Med. 2009;360:500-506.

Gowers SG. Management of eating disorders in children and adolescents. Arch Dis Child. 2008;93:331-334.

American Psychiatric Association. Treatment of patients with eating disorders, third edition. American Psychiatric Association. Am J Psychiatry. 2006;163(7 Suppl):4-54.

le Grange D, Lock J, Loeb K, Nicholls D. Academy for eating disorders position paper: The role of the family in eating disorders. Int J Eat Disord. 2009;43:1-5.

Fisher Ca, Hetrick SE, Rushford N. Family therapy for anorexia nervosa. Cochrane Database Syst Rev. 2010 Apr 14; (4):CD004780.

Update Date: 4/18/2012

Reviewed by: Fred K. Berger, MD, Addiction and Forensic Psychiatrist, Scripps Memorial Hospital, La Jolla, California. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.