Eating disorders aren't just about body weight. They also have to do with feelings and self-expression.

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Eating disorders are devastating mental illnesses that affect more than 7 million American women. Ninety percent of the people who suffer from the eating disorders anorexia nervosa and bulimia nervosa are women, according to the National Association of Anorexia Nervosa and Associated Disorders. Although they revolve around eating and body weight, eating disorders aren't about food, but about feelings and self-expression. Women with eating disorders use food and dieting as ways of coping with life's stresses. For some, food becomes a source of comfort and nurturing, or a way to control or release stress. For others, losing weight is a way to gain the approval of friends and family. Eating disorders are not diets, signs of personal weakness or problems that will go away without treatment.

Eating disorders occur in all socioeconomic and ethnic groups. Eating problems usually develop in girls between age 12 and 25. Age 17 is the average age that an eating disorder develops, and between five percent and 10 percent of young people have eating disorders. Because of the shame associated with this complex illness, many women don't seek treatment or get help until years later. Eating disorders also occur in older women and in men, but much less frequently.

Typically, women with eating disorders are described as having low self-esteem and feeling helpless and inadequate. There are several categories of eating disorders, including anorexia nervosa, bulimia nervosa and eating disorders not otherwise specified (EDNOS). All are considered psychiatric disorders.

Eating Disorders: Relentless Pursuit

Anorexia nervosa is a disorder in which preoccupation with dieting and thinness leads to excessive weight loss. If you suffer from this disease, you may not acknowledge that weight loss or restricted eating is a problem, and you may "feel fat" even when emaciated. Women with anorexia nervosa intentionally starve themselves or exercise excessively in a relentless pursuit to be thin, losing from 15 to 60 percent of their normal body weight. Half of all women suffering from anorexia nervosa never fully regain their health. A third remain chronically ill. About half of women with anorexia also suffer from bulimia.

Women with bulimia nervosa regularly and sometimes secretly binge on large quantities of food — up to 20,000 calories at one time — then feel intense feelings of guilt or shame and try to compensate by getting rid of the excess calories. Some purge by inducing vomiting, abusing laxatives and diuretics, or by taking enemas. Others fast or exercise to extremes. If you suffer from this disease, you feel out of control and recognize that your behavior is not normal but often deny to others that you have a problem. Women with bulimia can be any weight and often experience weight fluctuations. Bulimia is especially prevalent on college campuses where as many as 80 percent of female students have reportedly binged and purged at one time or another.

A third type of eating disorder, "eating disorders not otherwise specified" (EDNOS), refers to symptoms that don't fit into the other two categories of eating disorders. If you suffer from EDNOS, you are a compulsive eater who experiences uncontrolled and sometimes secretive eating.

Although it has become synonymous with eating disorders, anorexia is relatively rare, affecting less than 1 percent of adolescent women. Another 2 to 3 percent develop bulimia. Yet statistics don't tell the whole story. Many more women, who don't necessarily meet all the criteria for an eating disorder, are preoccupied with their bodies and caught up in destructive patterns of dieting and overeating that can seriously affect their health and well-being.