Eating disorders are so common in America that 1 or 2 out of every 100 students will struggle with one. Each year, thousands of teens develop eating disorders, or problems with weight, eating, or body image.

Eating disorders are more than just going on a diet to lose weight or trying to exercise every day. They're extremes in eating behavior — the diet that never ends and gradually gets more restrictive, for example. Or the person who can't go out with friends because he or she thinks it's more important to go running to work off a snack eaten earlier.

The most common eating disorders are anorexia nervosa and bulimia nervosa (usually called simply "anorexia" and "bulimia"). But other food-related disorders, like binge eating, body image disorders, and food phobias, are becoming more and more common.

Anorexia

People with anorexia have a real fear of weight gain and a distorted view of their body size and shape. As a result, they can't maintain a normal body weight. Many teens with anorexia restrict their food intake by dieting, fasting, or excessive exercise. They hardly eat at all — and the small amount of food they do eat becomes an obsession.

Others with anorexia may start binge eating and purging — eating a lot of food and then trying to get rid of the calories by forcing themselves to vomit, using laxatives, or exercising excessively, or some combination of these.

Bulimia

Bulimia is similar to anorexia. With bulimia, someone might binge eat (eat to excess) and then try to compensate in extreme ways, such as forced vomiting or excessive exercise, to prevent weight gain. Over time, these steps can be dangerous — both physically and emotionally. They can also lead to compulsive behaviors (ones that are hard to stop).

To be diagnosed with bulimia, a person must be binging and purging regularly, at least twice a week for a couple of months. Binge eating is different from going to a party and "pigging out" on pizza, then deciding to go to the gym the next day and eat more healthfully.

People with bulimia eat a large amount of food (often junk food) at once, usually in secret. Sometimes they eat food that is not cooked or might be still frozen, or retrieve food from the trash. They typically feel powerless to stop the eating and can only stop once they're too full to eat any more. Most people with bulimia then purge by vomiting, but may also use laxatives or excessive exercise.

Although anorexia and bulimia are very similar, people with anorexia are usually very thin and underweight but those with bulimia may be a normal weight or can be overweight.

Binge Eating Disorder

This eating disorder is similar to anorexia and bulimia because a person binges regularly on food (more than three times a week). But, unlike the other eating disorders, a person with binge eating disorder does not try to "compensate" by purging the food.

Anorexia, bulimia, and binge eating disorder all involve unhealthy eating patterns that begin gradually and build to the point where a person feels unable to control them.

Signs of Anorexia and Bulimia

Sometimes a person with anorexia or bulimia starts out just trying to lose some weight or hoping to get in shape. But the urge to eat less or to purge or over-exercise gets "addictive" and becomes too hard to stop.

Teens with anorexia or bulimia often feel intense fear of being fat or think that they're fat when they are not. Those with anorexia may weigh food before eating it or compulsively count the calories of everything. People to whom this seems "normal" or "cool" or who wish that others would leave them alone so they can just diet and be thin might have a serious problem.

How do you know for sure that someone is struggling with anorexia or bulimia? You can't tell just by looking — a person who loses a lot of weight might have another health condition or could be losing weight through healthy eating and exercise.

But there are some signs to watch for that might indicate a person has anorexia or bulimia.

Someone with anorexia might:

• become very thin, frail, or emaciated
• be obsessed with eating, food, and weight control
• weigh herself or himself repeatedly
• deliberately "water load" when going to see a health professional to get weighed
• count or portion food carefully
• only eat certain foods, avoiding foods like dairy, meat, wheat, etc. (of course, lots of people who are allergic to a particular food or are vegetarians avoid certain foods)
• exercise excessively
• feel fat
• withdraw from social activities, especially meals and celebrations involving food
• be depressed, lethargic (lacking in energy), and feel cold a lot

Someone with bulimia might:

• fear weight gain
• be intensely unhappy with body size, shape, and weight
• make excuses to go to the bathroom immediately after meals
• only eat diet or low-fat foods (except during binges)
• regularly buy laxatives, diuretics, or enemas
• spend most of his or her time working out or trying to work off calories
• withdraw from social activities, especially meals and celebrations involving food

What Causes Eating Disorders?

No one is really sure what causes eating disorders, although there are many theories about it. Many people who develop an eating disorder are between 13 and 17 years old. This is a time of emotional and physical changes, academic pressures, and a greater degree of peer pressure.

Although there is a sense of greater independence during the teen years, teens might feel that they are not in control of their personal freedom and, sometimes, of their bodies. This can be especially true during puberty.

For girls, even though it's completely normal (and necessary) to gain some additional body fat during puberty, some respond to this change by becoming very fearful of their new weight. They might mistakenly feel compelled to get rid of it any way they can.

When you combine the pressure to be like celebrity role models with the fact that bodies grow and change during puberty, it's not hard to see why some teens develop a negative view of themselves. Celebrity teens and athletes conform to the "Hollywood ideal" — girls are petite and skinny, and guys are athletic and muscular, and these body types are popular not only in Hollywood but also in high school.

Many people with eating disorders also can be depressed or anxious, or have other mental health problems such as obsessive-compulsive disorder (OCD). There is also evidence that eating disorders may run in families. Although part of this may be genetics, it's also because we learn our values and behaviors from our families.

Sports and Eating Disorders

Athletes and dancers are particularly vulnerable to developing eating disorders around the time of puberty, as they may want to stop or suppress growth (both height and weight).

Coaches, family members, and others may encourage teens in certain sports — such as gymnastics, ice skating, and ballet — to be as thin as possible. Some athletes and runners are also encouraged to weigh less or shed body fat at a time when they are biologically destined to gain it.

Effects of Eating Disorders

Eating disorders are serious medical illnesses. They often go along with other problems such as stress, anxiety, depression, and substance use. Eating disorders can lead to the development of serious physical health problems, such as heart conditions or kidney failure.

Someone whose body weight is at least 15% less than the average weight for that person's height may not have enough body fat to keep organs and other body parts healthy. In severe cases, eating disorders can lead to severe malnutrition and even death.

With anorexia, the body goes into starvation mode, and the lack of nutrition can affect the body in many ways:

• a drop in blood pressure, pulse, and breathing rate
• hair loss and fingernail breakage
• loss of periods
• lanugo hair — a soft hair that can grow all over the skin
• lightheadedness and inability to concentrate
• anemia
• swollen joints
• brittle bones

With bulimia, constant vomiting and lack of nutrients can cause these problems:

• constant stomach pain
• damage to the stomach and kidneys
• tooth decay (from exposure to stomach acids)
• "chipmunk cheeks," when the salivary glands permanently expand from throwing up so often
• loss of periods
• loss of the mineral potassium (this can contribute to heart problems and even death)

A person with binge eating disorder who gains a lot of weight is at risk of developing diabetes, heart disease, and some of the other diseases associated with being overweight.

The emotional pain of an eating disorder can take its toll, too. When someone becomes obsessed with weight, it's hard to concentrate on much else. It can be exhausting and overwhelming to monitor food intake and exercise, and be in a constant state of stress about food and how your body looks. It's easy to see why when you develop an eating disorder you could become withdrawn and less social. It gets too hard to join in on snacks and meals with friends or families, or too hard to stop the addictive exercising or working out to have fun.

Having an eating disorder also can use up a lot of mental energy planning what to eat, how to avoid food, planning a binge, getting money to buy food or laxatives or other medications, making up reasons to use the bathroom after meals, or figuring out how to tell people around you that you want to be alone after a meal.

Treatment for Eating Disorders

Fortunately, eating disorders can be treated. People with eating disorders can get well and gradually learn to eat well and more like their family and friends again. Eating disorders involve both the mind and body. So medical doctors, mental health professionals, and dietitians will often be involved in a person's treatment and recovery.

Therapy or counseling is a very important part of getting better — in many cases, family therapy is one of the keys to eating healthily again. Parents and other family members are important in supporting people who have to regain weight that they are afraid of, or to learn to accept the body shape that their culture, genes, and lifestyle allows for.

If you want to talk to someone about eating disorders but are unable or not ready to talk to a parent or close family member, try reaching out to a friend, teacher, school nurse or counselor, coach, neighbor, your doctor, or another trusted adult.

Remember that eating disorders are very common among teens. Treatment options depend on each person and their families, but many treatments incorporate journaling, talking to therapists, and working with dietitians and other professionals.

Learning to be comfortable at your healthy weight is a process. It takes time to unlearn some behaviors and relearn others. Be patient, you can learn to like your body, understand your eating behaviors, and figure out the relationship between feelings and eating — all the tools you need to feel in control and to like and accept yourself for who you are.

Reviewed by: Michelle New, PhD
Date reviewed: January 2011