Anorexia nervosa occurs in roughly 1/100 people. Someone with anorexia nervosa has both abnormally low body weight and an intense fear of gaining weight or becoming overweight. Anorexia nervosa is a serious and potentially life-threatening psychiatric condition, with the highest mortality rate of any mental illness.

There are two types of anorexia according to the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders. Restrictive anorexia nervosa is when you eat so little that you enter a state of starvation. Binge-purge anorexia nervosa involves repeatedly binge eating and then purging the food by vomiting or using laxatives, diuretics, or enemas. Binge/purge anorexia is different than bulimia nervosa. If you have binge/purge anorexia, your weight is very low whereas bulimia nervosa patients have body weights that are not critically low, but may still be unhealthy for that individual.

Typically, anorexia nervosa begins in adolescence or earlier when the bodies of young people are changing. Youth are especially vulnerable to developing a distorted body image and self-esteem. Girls are about six times more likely than boys to be diagnosed with anorexia. This may be partly because it is difficult to identify eating disorders in males.

Causes and Symptoms

If you or a loved one has anorexia, you may also have a related psychological illness such as depression, anxiety, or obsessive-compulsive disorder. You may tend to withdraw from social situations, show signs of irritability, experience insomnia, or feel compelled to engage in safety behaviors to prevent or reduce anxiety.

People with anorexia nervosa may experience physical, emotional, and behavioral symptoms. Behavioral symptoms can include:

• Distorted beliefs about body shape and weight
• Engaging in excessive exercise
• Severely restricting food intake
• Self-induced vomiting
• Taking laxatives, diuretics, or diet pills

Emotional symptoms can be:

• Avoiding mealtimes or situations involving food
• Complaining about "being fat" or having parts of the body that are "fat"
• Cooks meals for others without eating
• Covering up in layers of clothing to either hide weight loss or stay warm
• Denial of hunger or making excuses for not eating
• Eating only a few "safe" foods, usually those that are low in fat and calories
• Fear of gaining weight that can include repeated weighing or measuring the body
• Flat mood (lack of emotion) or difficulty labeling this emotion
• Focus on weight, food, calories, fat grams, and dieting
• Frequently skipping meals or refusing to eat
• Having rigid meal or eating rituals, such as cutting up food into tiny pieces
• Insomnia
• Irritability
• Lying about how much food you have eaten
• Not wanting to eat in public
• Often checking in the mirror for perceived flaws
• Preoccupation with food, which can include cooking elaborate meals for others but not eating them
• Social withdrawal or limited spontaneity
• Reduced interest in sex or any physical contact

Physical symptoms can include:

• Cavities, or discoloration of teeth, from vomiting
• Cold, spotted hands and feet or swelling of feet
• Cuts or calluses on the tops of finger joints (as a result of inducing vomiting)
• Dental problems, such as enamel erosion, cavities, and tooth sensitivity
• Difficulty concentrating
• Dizziness
• Dry skin
• Dry and brittle nails
• Fainting
• Feeling cold all the time
• Fine hair on body (lanugo)
• Impaired immune functioning
• Menstrual irregularities
• Muscle weakness
• Poor wound healing
• Sleeping difficulties
• Swelling around area of salivary glands
• Thinning of hair on head or dry and brittle hair 
• Indigestion or chronic stomach pains and discomfort

Complications

People who have anorexia nervosa lose an extreme amount of weight. This can lead to dangerous health problems, such as:

• Growth delay in children
• Heart and kidney dysfunction
• Infertility
• Osteoporosis

Diagnosis

If your doctor thinks you or a loved one might have anorexia nervosa, the first step is to find out if there is another cause for the weight loss. This usually involves a physical exam, blood tests and other lab tests, and a psychological evaluation. Doctors may also use other diagnostic tests, such as an electrocardiogram.

If you do not appear to have another reason for weight loss, your doctor will perform a more thorough exam. This will likely include a complete medical history and detailed physical exam. We will take a diet history that addresses what you eat and how you think about food and nutrition. Your doctor may also ask about body image and weight loss history.

There is no lab test to diagnose anorexia nervosa, but patients must meet three criteria:

• Weigh less than the normal minimum for age, sex, stage of growth and development, and physical health
• Have an intense fear of gaining weight or "becoming fat" despite being below weight or at significantly low weight
• Show a disturbance in the way they view their body weight or shape

Treatment

At the Center of Excellence in Eating and Weight Disorders at Mount Sinai, we offer a variety of effective interventions for anorexia nervosa. Most of these are family-based treatments. Treatments do not work in the same way for everyone. For some, a single course of treatment is effective. Others may gain weight and recover—and then lose weight and relapse.

You may need frequent monitoring of certain vital signs and physical conditions. This could include hydration and electrolyte levels. We will also focus on getting you back to a healthy weight.

Anorexia vs. Bulimia

Anorexia and bulimia are the most well know eating disorders. They both involve a distorted body image and are similar in many ways. There is one major difference, though. If you have anorexia, your weight is extremely low. By contrast, patients with bulimia are often in a normal weight range, but may be low for that individual (e.g., semi-starved state).

The Term "Anorexia Nervosa"

You may wonder about the term anorexia nervosa. The term “anorexia” comes from Greek and means without appetite. Nervosa is Latin for nervous. Together, the phrase means a nervous absence of appetite. The condition is nothing new; even the name for it has been around since the mid-to-late 1800s.