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Anorexia Nervosa


The Manual's Editorial Staff

Reviewed/Revised Mar 2022 | Modified Sep 2022
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What is anorexia nervosa (anorexia)?

Anorexia is an eating disorder. If you have anorexia, you're obsessed with becoming thinner even if you're already underweight. This obsession makes you do one of two things:

  • Eat very little

  • Eat a lot at one time (binge eat) and then make yourself throw up (purge)

As a result you lose more weight than is healthy for your age and size. You may lose so much weight you become seriously ill or even die. Despite looking thin and ill, you stay convinced you're too fat.

Anorexia may be caused by social pressures to be thin. The disorder can run in your family.

What are the symptoms of anorexia?

When you have anorexia, your whole life revolves around how much you eat and how much you weigh. You're so convinced you're fat that you may not eat enough food. Sometimes you may eat a huge amount at once and then make yourself throw up. Even as you get too thin, you want to be even thinner. You may:

  • Complain about being overweight, even though you’re very thin

  • Think about food all the time

  • Measure your food and count calories

  • Hoard, hide, or throw away your food

  • Skip meals

  • Pretend to eat or lie about how much you’ve eaten

  • Exercise a lot more than usual

  • Wear bulky clothes or lots of layers

  • Weigh yourself many times a day

  • Feel good about yourself based on how thin you think you look

What problems can anorexia cause?

Anorexia isn't just about looking too thin. If you lose too much weight, you can damage your whole body. Anorexia may cause:

  • In women, your period to stop

  • In women, hair to grow on your face and body

  • Swelling or bloating

  • Belly pains

  • Constipation (trouble pooping)

  • Depression

If you make yourself throw up a lot, the stomach acid will damage your teeth. If anorexia gets very bad, it can affect the chemical balance in your body, which can cause thinning of your bones, serious heart problems, or even death.

Who can get anorexia?

Anyone can get anorexia. It's more likely to start in the teen or young adult years. It's much more common in girls and women.

People with anorexia are often able to hide it from their loved ones. This means that family and friends may not know about it until it’s very bad and life-threatening. Learning the symptoms of anorexia can help you recognize it in someone you love.

How can doctors tell if I have anorexia?

Doctors will check your height and weight to see if you weigh too little for how tall you are. They’ll also ask you how you feel about your body and your weight.

If anorexia seems likely, doctors will do a physical exam. They'll order blood and urine tests to check for problems caused by anorexia. A test to check for thinning of your bones and a test for abnormal heart rhythms may also be done.

How do doctors treat anorexia?

Treatment to change eating habits

Doctors will have you see a mental health provider for therapy. Therapy for anorexia:

  • Focuses on learning healthy eating habits and reaching a healthy weight

  • Can be one-on-one or family-based (family therapy is especially helpful for teens)

  • May go on for up to 2 years after you've regained weight

Treatment to regain weight

If you've lost a lot of weight or lost weight very quickly, doctors will try to help you regain weight. This may involve:

  • A hospital stay to make sure you eat enough

  • Regular doctor check-ups

  • Visits with a nutritionist (a health care provider who focuses on healthy eating)

Sometimes doctors give you medicines to treat anxiety and depression. When your mood is better, you may eat more and gain weight.

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