Anorexia, bulimia, binge eating explained
 

by Julia Litzky '12
SCIENCE EDITOR

In the U.S., over 10 million women and one million men are currently struggling with an eating disorder. These disorders are especially prevalent among college-aged women, since the average age of onset is between 17 and 20 years old. In addition to these disorders, about a third of college-aged women have disordered eating habits, characterized by excessive dieting and exercise.

Anorexia, which involves self-starvation, is the most dangerous eating disorder. At least one in 10 anorexics die from the effects of starvation. The mortality rate among anorexics is 12 times higher than any other cause of death among women between the ages of 15 and 24. Symptoms to watch for are dramatic weight loss, an obsession with food, counting calories, dieting, frequent discussion of feeling fat or fear of becoming fat, rituals involving food, excessive exercise and withdrawal from friends.

The medical definition of anorexia involves having a body mass index below 18.5 and, for women, missing their menstrual cycle for several months (which happens when a woman’s body senses that she does not have the fat stores to carry a child). Being very underweight is dangerous because the body must break down muscle tissue in order to acquire energy, instead of the fat it would normally use. Since the diaphragm and heart are muscles, this can severely affect their function. Additionally, not eating means not getting enough nutrients and vitamins. This can result in imbalances in electrolytes, which can lead to heart attacks. A lack of calcium leads to reduced bone density (osteoporosis), which results in brittle bones that break easily. Additionally, dehydration can lead to kidney failure; the overuse of laxatives and diuretics, which is frequent in anorexics, adds to this dehydration.

The causes of anorexia are still unknown, but anorexics’ brains have been found to process the taste of food differently than non-eating-disordered individuals. Additionally, anorexics seem to be more concerned with their choices’ consequences than the immediate pleasure they could attain from a choice. However, these differences could be a result of the disease instead of the cause. Either way, antidepressants have been found to be helpful in treating the disorder, and 70 percent of women with anorexia recover by the age of 30, usually within three to five years of the onset of the disorder. Still, half of anorexics will develop a second eating disorder, bulimia, before recovering.

Bulimia, which involves a cycle of binge eating followed by self-induced vomiting, abuse of diuretics or laxatives and fasting or exercising excessively, seems to be the result of reduced tryptophan levels in the brain. Since tryptophan is required for serotonin production, and serotonin controls both happiness and appetite, lacking tryptophan can severely affect eating habits and depression. Like anorexics, bulimics tend to withdraw from their friends, exercise excessively and obsess over controlling food and weight. However, there are also clearer signs of bulimia, such as swollen cheeks or jaw, cuts on the knuckles or back of the hands, stained or discolored teeth and frequent trips to the bathroom, especially after eating.

Like anorexia, bulimia can be deadly. Frequent vomiting disrupts the electrolyte balance in the body, leading to the development of an irregular heart rate, which can result in heart failure and death. Since bulimics can eat up to 20,000 calories in one binge, they can rupture their gastric system, and the frequent vomiting can result in ruptures of the esophagus, ulcers and tooth decay, from stomach acids.

The third, and lesser-known eating disorder is binge eating disorder, sometimes called compulsive overeating. It is characterized by frequently eating large amounts of food and then feeling guilty or disgusted by having done so. Often, eating is done in secret, and not necessarily when the person is hungry. The disorder is strongly linked with depression. Eating increases serotonin levels in the brain, and this decreases depression, but the effect is short-lived. Since this disorder results in overeating, the most dangerous side-effects are those that result from clinical obesity, including high blood pressure, high cholesterol, diabetes and heart disease.
The goal of NEDAW is to help students understand eating disorders and body image issues such as these.