Dieting and concern about body image are an American pastime. At any given moment, some 50 million Americans are on a weight-loss regimen. Although few of those who wish they were thinner suffer from a true psychiatric eating disorder, the number of individuals who have either of the two major forms of eating disorders - anorexia nervosa and bulimia - has risen dramatically in recent decades.
obesity is sometimes considered a third eating disorder. Technically, it is not viewed as a true psychiatric problem, unless attempts to lose weight become abnormally obsessive or concern about body image becomes so severe that it interferes with normal functioning and good mental health. These emotional problems frequently accompany obesity.
Anorexia nervosa (severe self-starvation) and bulimia (binge-eating and purging) have striking, sometimes life-threatening physical features that must be treated medically. The roots of these disorders are emotional and psychological and treatment approaches are primarily psychological. While investigators do not agree on the causes of these disorders, numerous factors that contribute to their development have been identified.
Ordinarily, bulimia begins between the ages of 17 and 25, however, because many bulimics are deeply ashamed of their bingeing and purging and keep these activities a secret, an actual diagnosis may not be made until a patient is well into her 30s or 40s.
Bulimia usually begins in conjunction with a diet, but once the binge-purge cycle becomes established, it can get out of control. Some bulimics may be somewhat underweight and a few may be obese, but most tend to keep a normal weight. In many, the menstrual cycle becomes irregular. Sexual interest may diminish. Bulimics may exhibit impulsive behaviors, such as shoplifting, alcohol and drug abuse. Many appear to be healthy and successful perfectionists at whatever they do. Actually, most bulimics have very low self-esteem and are often depressed.
To lose the gained weight, the bulimic begins purging, which may include using laxatives or diuretics (drugs to increase urination), self-induced vomiting caused by gagging, using an emetic (a chemical substance that causes vomiting) or simply mentally willing the action. Between binges, the person may fast or exercise excessively.
The bulimia binge-purge cycle can be devastating to health in a number of ways. It can upset the balance of electrolytes - sodium, magnesium, potassium and calcium - which can cause fatigue, seizures, muscle cramps, irregular heartbeat and decreased bone density (leading to osteoporosis). Repeated vomiting can damage the esophagus and stomach, cause the salivary glands to swell, make gums recede and erode tooth enamel. In some cases, all teeth must be pulled prematurely because of the constant wash by gastric acid. Other effects may be rashes, broken blood vessels in the cheeks, and swelling around the eyes, ankles and feet. For diabetics, bingeing on high-carbohydrate foods and sweets is particularly hazardous since their bodies cannot properly metabolize the starches and sugars.
The individual with anorexia nervosa is usually someone of normal or slightly above normal weight who starts on an "innocent" diet and eventually begins suppressing hunger sensations (to the point of self-starvation). There is frequently a history of someone in the family who is a dieter, overweight or focused on staying slim and fit.
Although the illness is most common among teenage or young adult women, it can also affect males, preadolescents, older adults and individuals from different ethnic and cultural backgrounds. Classic anorectics starve themselves to skeletal thinness, losing more than 15 percent (frequently 25 to 35 percent) of their original body weight. This dramatic weight loss is usually accompanied by an intense fear of gaining weight or becoming obese that does not diminish as weight loss progresses. Other characteristics of the disorder include a distorted body-image (indicated by the individual's claims of being fat, even when emaciated), a refusal to maintain body weight over minimum normal weight for age and height, and the loss of menstrual periods.
The causes of anorexia nervosa are unknown. The widespread emphasis on diets and the desire for thinness in our society contribute to its high incidence, and psychological factors play an important role in its development.