Anorexia Nervosa

What anorexia nervosa is

Anorexia is a mental illness with serious physical effects. The core features are:

• restriction of energy intake leading to significantly low body weight for age, sex and development, or failure to gain expected weight in children
• intense fear of gaining weight or persistent behavior that prevents weight gain
• disturbed body image, an outsized influence of weight on self-worth, or not recognizing how serious the low weight is

There are two subtypes: restricting type, with dieting, fasting or excessive exercise, and binge-eating/purging type, with episodes of binge eating or purging by vomiting, laxatives or diuretics.

Atypical anorexia describes people with all the features except low weight, because they started at a higher weight. Medical risks can be just as serious.

Warning signs

Behavioral signs

• skipping meals, eating very small portions, cutting out food groups
• rigid rules and rituals around food, cutting food into tiny pieces
• preoccupation with calories, labels, recipes or cooking for others without eating
• excessive or compulsive exercise
• wearing baggy clothes, frequent weighing or body checking
• withdrawal from friends and social eating
• going to the bathroom right after meals

Physical signs

• significant weight loss or failure to grow
• feeling cold all the time, cold hands and feet
• dizziness, fainting and tiredness
• missed or stopped periods
• dry skin, brittle nails, thinning hair and fine downy body hair (lanugo)
• constipation and bloating
• poor sleep and difficulty concentrating

Emotional signs

Anxiety, low mood, irritability, perfectionism and denial that anything is wrong are common. Many people also have depression, anxiety disorders or obsessive-compulsive disorder.

Causes and risk factors

Anorexia results from a mix of genetic, biological, psychological and social factors:

• a family history of eating disorders, depression, anxiety or substance use; twin studies suggest genes account for about half the risk
• personality traits: perfectionism, anxiety, rigidity
• dieting, which often triggers onset
• puberty and life transitions
• sports or activities emphasizing weight or appearance: ballet, gymnastics, running, wrestling, modeling
• trauma, bullying and weight-related teasing
• type 1 diabetes, autism and some other conditions

Health risks

Starvation affects every organ.

See osteoporosis for more on bone health.

Diagnosis

A doctor will take a history of eating, weight, exercise and purging, and ask about mood and thoughts of self-harm. Examination includes weight, height, body mass index (or growth charts in children), heart rate, blood pressure lying and standing, and temperature. Tests include:

• blood tests: electrolytes, phosphate, magnesium, kidney and liver function, blood count, glucose and thyroid
• ECG to check heart rate and rhythm
• bone density scan if periods have been absent for 6 months or more

Treatment

Treatment is usually led by a team: physician, therapist, dietitian and psychiatrist.

Medical stabilization and nutrition

Weight restoration is essential, as many psychological symptoms improve only once nutrition is restored. Refeeding starts carefully in severely malnourished people, with blood tests to watch for refeeding syndrome, a dangerous drop in phosphate and other minerals. Hospital admission may be needed for very low weight, unstable vital signs, abnormal blood tests or refusal of food.

Psychological therapy

• Family-based treatment (FBT): the first-line approach for children and teenagers. Parents take charge of meals at home with guidance, then gradually return control.
• Enhanced cognitive behavioral therapy (CBT-E) for adults.
• Maudsley Anorexia Nervosa Treatment for Adults (MANTRA) and specialist supportive clinical management.

Levels of care

Outpatient, intensive outpatient, partial hospitalization (day programs), residential treatment and inpatient hospital care, depending on severity.

Medicines

No medicine treats anorexia itself. Antidepressants may help co-existing depression or anxiety after weight is restored. Low-dose olanzapine is sometimes used to reduce anxious, obsessive thinking.

Outlook

About half of people make a full recovery and many more improve, though relapse is common, especially in the first year. Recovery can take several years. Early treatment, especially within the first 3 years, and family involvement in younger people improve outcomes.

How to help someone with anorexia

• Choose a calm, private moment to express concern about specific behaviors, not appearance.
• Avoid comments about weight, food or bodies.
• Expect denial or anger, and keep the door open.
• Encourage a doctor visit and offer to go with them.
• For a child or teen, seek help promptly through their primary care doctor.

Frequently asked questions

What are the first signs of anorexia?

Early signs often include strict dieting, cutting out food groups, skipping meals, preoccupation with calories, excessive exercise, avoiding eating with others and weight loss or failure to gain weight in a growing child. Irritability, anxiety around meals and missed periods may follow.

Can you have anorexia without being underweight?

Yes. People who start at a higher weight can lose a large amount and still be in a "normal" weight range. This is called atypical anorexia. It carries the same psychological symptoms and can cause serious medical complications such as a slow heart rate.

What is the most effective treatment for anorexia?

For children and teenagers, family-based treatment has the strongest evidence. For adults, enhanced CBT and other specialist therapies are recommended. In all cases, restoring nutrition and weight under medical supervision is essential.

Can people fully recover from anorexia?

Yes. Many people recover fully, especially with early, specialized treatment. Recovery usually takes time, often several years, and relapse can happen, but long-term follow-up and support improve the chance of lasting recovery.

Is anorexia dangerous?

Yes. Anorexia has the highest mortality of any mental illness, mainly from heart problems and suicide. It can also cause lasting bone loss and fertility problems. These risks are why prompt medical and psychological treatment is important.