Anorexia Nervosa

What is anorexia nervosa?

Anorexia nervosa, or simply "anorexia," is a form of self-starvation, a complicated eating disorder with medical, behavioral and psychological components.

It’s characterized by low body weight (less than 85 percent of the normal weight for the child’s height and age), a distorted body image and an intense fear of gaining weight. Many teens and their families struggle with anorexia nervosa. Eating disorders are the third most common chronic disease in the U.S. An estimated 0.5 percent of 15- to 19-year-olds have anorexia nervosa.

There are two subgroups of anorexic behavior. Both have the goal of reducing calories:

  • Restricting type: An adolescent severely limits the intake of food, especially food that contains fat.
  • Binge/purge type: An adolescent restricts intake and may then have a binge followed by a purging of calories.

Anorexia, and the malnutrition that results, can damage nearly every organ system in the body, and may be fatal. Early diagnosis and treatment are extremely important.

Anorexia is a serious disease. It can affect many systems of your child’s body, including:

  • Cardiovascular (heart): Complications may include mitral valve prolapse (a floppy valve in the heart), arrhythmias (a fast, slow or irregular heartbeat), bradycardia (slow heartbeat), hypotension (low blood pressure) and heart failure.
  • Hematological (blood): About one-third of anorexic adolescents have mild anemia (low red blood cell count). Leukopenia (low white blood cell count) occurs in up to 50 percent of anorexic adolescents.
  • Gastrointestinal (stomach and intestines): Normal movement in the intestinal tract often slows down with very restricted eating and severe weight loss. Gaining weight, and taking certain medications, can help to restore your child’s normal intestinal function.
  • Renal (kidney) : Anorexia may cause dehydration, which can result in highly concentrated urine. Polyuria (increased production of urine) may also develop in anorexic patients when the kidneys start to lose their ability to concentrate urine. These changes usually return to normal when your child gets back to a normal weight.
  • Endocrine (hormones): One of the most telling symptoms of anorexia is amenorrhea, or when the menstrual cycle is missed for three or more consecutive cycles without any other underlying cause. Amenorrhea may appear before your child loses any amount of weight, and continue after her normal weight is restored. Adolescents with anorexia may also have lower levels of growth hormone, which may explain their failure to grow normally. Luckily, normal nutrition usually restores normal growth.
  • Skeletal (bones): If your child has anorexia, they are at an increased risk for low bone density. If the anorexic behavior has started before the bones have been fully formed (usually mid to late teens), there is a greater risk of osteopenia (decreased bone tissue) or osteoporosis (bone loss) or fractures.

How we care for anorexia nervosa

The Eating Disorders Program at Children’s Hospital Boston provides comprehensive evaluation and treatment services every year to more than 200 adolescents with anorexia nervosa, bulimia nervosa and related eating disorders. Staffed by expert specialists, the program addresses your child’s medical, nutritional and psychological needs in order to effectively treat the disorder.