An eating disorder is a mental and physical illness that is characterized by a preoccupation with food and weight. This condition is often so serious that the person with the eating disorder is able to focus on very few things other than the food they eat, how much they weigh, and how they appear to others. For example, a person with an eating disorder may eat extremely small amounts of food or none at all. They may also spend hours looking at themselves in the mirror. A person with another type of eating disorder may overeat or eat in secret.

Many people with an eating disorder also face other illnesses. These are called co-morbidities, or diseases that coexist with the eating disorder. For people with an eating disorder, these other illnesses often include depression, anxiety disorders, and substance abuse.

The path from a normal, healthy diet to an eating disorder is sometimes a very perplexing one. While the exact cause is unknown, certain factors may play a role in the development of an eating disorder. This could include emotional issues like low self-esteem or impulsive behavior. Traumatic events, abuse, or pressure to conform to society’s definition of beauty may also trigger a shift toward unhealthy behaviors.

Eating disorders may begin slowly, with crash diets or overindulging from time to time. At some point, these habits of eating less or eating more begin to spiral out of control. The desire and drive to eat less or more is blown out of proportion. This leads to an unhealthy relationship with food and the body.

An eating disorder may first appear during a person’s teenage or young adult years. However, an eating disorder can develop at any time in life. This means children and even elderly individuals may be at risk for an eating disorder.

Both men and women are both affected by eating disorders. However, this condition is more common among women and young girls. Men with an eating disorder may go undiagnosed because it’s often falsely considered a female-only condition.

According to the National Eating Disorders Association (NEDA), as many as 10 million people in the United States have an eating disorder. (NEDA, 2005)

Anorexia nervosa

People with anorexia nervosa are unusually obsessed with or fixated on eating, food, and weight control. They have an irrational fear of gaining weight. Many of these people see themselves as overweight or obese, even when confronted with evidence that they are underweight and malnourished.

It’s not uncommon for people with anorexia to weigh themselves repeatedly, even multiple times in one day. They may also obsessively portion their food and eat very small quantities when they do eat.

Anorexia nervosa is the least common eating disorder. According to the National Institutes of Health (NIH), less than one percent of Americans will have the illness in their lifetimes. The average onset for the illness is 19 years old. However, it is the most deadly of the three main eating disorder types. (NIH, 2007)

Anorexia nervosa may cause side effects or additional health problems. These include:

  • anemia
  • brittle hair and nails
  • constipation
  • dry, yellow-tinted skin
  • feeling lethargic or tired frequently
  • infertility
  • lack of menstruation (period) among females
  • lanugo, or fine hair growth that covers the body
  • low blood pressure
  • lowered internal body temperature. This may cause the person to feel cold all the time.
  • muscle weakness
  • slowed breathing and pulse

If left untreated, anorexia nervosa may begin to cause more serious complications. These include:

  • osteoporosis
  • brain damage
  • heart damage
  • organ failure
  • death. According to the National Institute of Mental Health (NIMH), people with anorexia nervosa are 18 times more likely to die early compared with people of the same age who do not have an eating disorder. (NIMH, 2011)

Bulimia nervosa

People with bulimia nervosa frequently eat large amounts of food at one time, often in private. This is called binge eating. People with this disorder feel as if they have no control over their eating behaviors. To compensate, the person will then engage in excessive exercise, self-induced vomiting, or fasting. He or she may even use diuretics, laxatives, or an enema.

Unlike people with anorexia nervosa, people with bulimia nervosa may appear to be a healthy, average weight. They still fear gaining weight or being obese or overweight, and they are often very unhappy with how they look. Their goal to lose weight, look a certain way, or be a particular size becomes an obsession.

Approximately one percent of the U.S. population will have bulimia nervosa in their lifetime. The average age of onset for the illness is 20 years old. (NIH, 2007)

The physical side effects of bulimia nervosa include:

  • acid reflux disorder
  • chronically sore or inflamed throat
  • dehydration from purging fluids and vomiting
  • electrolyte imbalance. Vomiting and purging can lead to too-low or too-high levels of sodium, calcium, potassium, and other minerals. If electrolyte levels get too low, it may cause a heart attack.
  • gastrointestinal problems
  • intestinal irritation from laxative abuse
  • swollen salivary glands
  • sensitive teeth that is the result of exposure to stomach acid
  • worn or decaying tooth enamel

Binge-eating disorder

People with a binge-eating disorder do not have control over how much they eat. A person with a binge-eating disorder consumes excessive amounts of food on a regular basis, often to the point of discomfort and pain. People who binge may eat when they’re not hungry, and they will often continue eating long after they’re full. However, unlike bulimia nervosa, people with a binge-eating disorder do not engage in behaviors of purging, fasting, or excessive exercise to get rid of the food.

People with a binge-eating disorder are often obese or overweight. For that reason, these people are often at a higher risk for developing cardiovascular disease and high blood pressure. Many experience psychological issues as a result of their illness, too. They often deal with shame about their binge-eating behavior. This guilt has a cyclical effect that can lead to more binge eating.

Binge eating is more common than anorexia nervosa or bulimia nervosa. In the United States, 2.8 percent of adults will have the eating disorder in their lifetime. The average age of onset is 25 years old. (NIH, 2007)

Another category of eating disorders is known as Eating Disorders Not Otherwise Specified (EDNOS). EDNOS is an umbrella term for any eating disorder that is neither anorexia nor bulimia nervosa. Binge eating is a type of EDNOS.

While different types of eating disorders may manifest similar behaviors, the physical signs and symptoms will vary based on the type and severity of the eating disorder.

What Are the Signs of Anorexia Nervosa?

People with anorexia nervosa have an unhealthy obsession with food and being skinny. If left untreated, this condition can reach the point of starvation. This can cause organ failure and even death.

Behaviors associated with anorexia nervosa include:

  • a distorted body image
  • an intense fear of gaining weight
  • a relentless pursuit of being thin, even at the cost of being healthy or at a normal weight
  • extremely restricted eating behaviors
  • extreme exercise patterns
  • refusal to eat
  • denial of hunger
  • fear of eating in public
  • being preoccupied with food

What Are the Signs of Bulimia Nervosa?

People with bulimia nervosa may appear to be at a normal weight. They may also be slightly overweight.

The physical signs and symptoms of bulimia nervosa include:

  • leaving during meals or shortly after meals to go to the bathroom
  • sores or calluses on the hands and knuckles
  • sensitive teeth that is the result of exposure to stomach acid
  • worn or decaying tooth enamel