What is Anorexia Nervosa?

Anorexia nervosa (AN) is an eating disorder in which a person is at an extremely low body weight but fears gaining weight. A person with AN may also experience their body as heavier or bigger than it truly is. They may also consider their body weight and/or shape to be one of the most important things that determines their self-worth or self-esteem. They may not realize how medically dangerous being underweight is for their health.

AN is a serious mental health disorder that affects a person's physical and mental health. Over time, these behaviors can cause serious damage to the body. In some cases, the behaviors can lead to death.

What Are the Different Types of AN?

The two types of AN include:

  • Restricting type is when a person with AN only restricts or limits how much food they eat. They eat far fewer calories than needed to keep a healthy body weight.
  • Binge-eating/purging type is when a person with AN sometimes feels out of control when they eat. They might also use certain purging behaviors, such as vomiting, use of laxatives or diet pills to make up for the calories they eat.

Which Risk Factors Can Raise a Person's Risk of Developing AN?

There can be many factors that raise a person's risk of developing AN, including one or more of the following:

  • Certain psychological traits (such as perfectionism, obsessive-compulsive behaviors, anxiety or depression)
  • Genetics or a family history of AN
  • Environmental factors (such as peer pressure, being around friends and family who diet or the media's focus on being thin)

Who Is Most Likely to be Affected by AN?

Anyone of any gender can be affected by AN.Certain groups of people may be more likely to be affected than others, such as:

  • Young women
  • People who identify as transgender
  • Female athletes in sports that encourage being thin (such as gymnastics or dance)

What are the Signs of AN?

  • Skipping meals, denying hunger or making excuses not to eat
  • Extreme weight loss
  • Leaving to use the bathroom right after meals or staying in the bathroom for long periods of time
  • Exercising when it seems unsafe to do so
  • Dressing in layers to hide the body and/or keep warm
  • Calling themselves fat despite losing weight or being underweight
  • Special eating or mealtime rituals (such as excessively chewing food or eating foods in a certain order)
  • Fixation with calories or the fat content of food
  • Social isolation or withdrawal

In severe (very bad) cases, a person can develop malnutrition (poor health because of a lack of calories or nutrients). Signs of malnutrition include:

  • Insomnia (trouble sleeping)
  • Fatigue (extreme tiredness), dizziness or fainting
  • Stomach cramps or other abdominal (belly area) pain
  • Hair loss or thinning of hair
  • Osteoporosis (weakening of the bones)
  • In women and girls, loss of a menstrual period (also called amenorrhea) or delayed period (if they have not started it yet)

How Do Doctors Diagnose AN?

Doctors can diagnose AN with the following tests:

  • Physical exam
  • Asking questions about your child's eating habits and behaviors
  • Blood tests
  • Imaging tests of the bones
  • Interview with a mental health provider about eating behaviors and body image and weight concerns

How Do Doctors Treat AN?

Treatment focuses on helping your child reach a healthy weight and addressing psychological concerns of AN. The care team will talk with you about creating a treatment plan for your child's medical and mental health needs.

Common treatments supported by research for AN include:

  • For children and teens, family-based therapy (FBT) to learn ways on how your family can support your child during AN treatment
  • For young adults, cognitive behavioral therapy (CBT) to help manage your child's thoughts, feelings, and behaviors around AN and body image
  • Meetings with your child's primary care provider or a dietitian
  • For some people, a higher level of care such as hospitalization or residential care is needed to support a person in gaining weight and staying medically stable.

AN can be challenging to treat. The care team can help you and your child create a plan that raises the chances of recovery.

Rev. 12/2018. © 2020 MGHfC. This document is intended to provide health related information so that you may be better informed. It is not a substitute for a doctor's medical advice and should not be relied upon for treatment for specific medical conditions