Eating disorders develop
through a variety of familial
and cultural factors.
Adolescents. Anorexia nervosa, in which dieting is carried to a dangerous extreme, is rare before puberty. It typically strikes girls between 12 and 17. The most telltale symptom is dramatic weight loss. Anorexics complain of feeling fat, even as the pounds melt away. Eventually, menstruation ceases and there may be growth of fine body hair. They often are compulsive exercisers. Work, school, and social obligations are structured around workouts.
Bulimia usually appears in the late teens and early 20s. It's more difficult to recognize because bulimics often have a normal weight and may eat regular meals. They try to control their weight through a vicious cycle of binge eating, vomiting (often called purging), or overuse of laxatives. It's estimated that 3 percent of college-age women are bulimic.
Girls. Girls and women represent about 90 percent of patients at eating disorder clinics. No one can fully explain this gender imbalance, but it probably stems from cultural pressure for girls to be thin, says Dr. Humphries. Girls who hear negative comments or teasing remarks about their weight are at particularly high risk for developing an eating disorder.
Whites. Cultural differences may also account for differing attitudes and experiences among African-American and white girls. Although all girls at 10 have an equal desire to lose weight, a lower percentage of African-American girls suffer eating disorders as teenagers when compared with white girls. George Schreiber, of Westat, Inc., a research firm in Rockville, Maryland, thinks it's because they don't strive to be impossibly thin and are more tolerant of being heavier.
"Black girls always choose a heavier-designed body image than white girls," he says. "And at every level, white girls are more dissatisfied with their bodies than black girls."
Dieters. Going on a diet is often what starts an eating disorder, says Victor Fornari, MD, director of the Center for Eating Disorders at North Shore University Hospital in Manhasset, New York. "We often hear patients say, 'I began to diet to lose 5 or 10 pounds, and then the diet controlled me,'" he says.
At least one prominent researcher, though, cautions against assuming this preoccupation will lead to an epidemic of anorexia. "Lots of people diet, but not everybody gets an eating disorder," argues Walter H. Kaye, MD, director of the Eating Disorders Module at the University of Pittsburgh Medical Center.
Children of heavy parents. New research strongly suggests heredity may be involved in the development of some eating disorders. Identical twins are much more likely to share the problem than fraternal twins.
"There's pretty compelling evidence for genetics," says Dr. Kaye. "It's possible that eating disorders are an interaction of both genetics and culture."