Bulimia nervosa is defined as two or more episodes of binge eating (rapid consumption of a large amount of food, up to 5,000 calories) every week for at least three months. The binges are sometimes followed by vomiting or purging and may alternate with compulsive exercise and fasting. The symptoms can develop at any age from early adolescence to 40, but usually become clinically serious in late adolescence.
Bulimia is not as dangerous to health as anorexia, but it has many unpleasant physical effects, including fatigue, weakness, constipation, fluid retention, swollen salivary glands, erosion of dental enamel, sore throat from vomiting, and scars on the hand from inducing vomiting. Overuse of laxatives can cause stomach upset and other digestive troubles. Other dangers are dehydration, loss of potassium, and tearing of the esophagus. These eating disorders also occur in men and older women, but much less frequently. Women with diabetes, who have a high rate of bulimia, often lose weight after an eating binge by reducing their dose of insulin. According to recent research, this practice damages eye tissue and raises the risk of diabetic retinopathy, which can lead to blindness.
Many anorectic women also indulge in occasional eating binges, and half of them make the transition to bulimia. About 40% of the most severely bulimic patients have a history of anorexia. It is not clear whether the combination of anorexia with bingeing and purging is more debilitating, physically or emotionally, than anorexia alone. According to some research, anorectic women who binge and purge are less stable emotionally and more likely to commit suicide. But one recent study suggests that, on the contrary, they are more likely to recover.
The exact cause of the disorder is unknown, but a variety of psychological, social, cultural, familial and biochemical theories are being investigated. Bulimia has been recognized for a much shorter time than anorexia, and there is less research on its origins. One theory is that bulimic women lack all the parental affection and involvement they need and soothe them with food as compensation. The overeating subdues feelings of which they are barely conscious, at the price of later shame and self-hatred. One recent study found that bulimic women differed from depressed and anxious women in several ways. They were more likely to be overweight, to have overweight parents, and to have begun menstruating early. They were also more likely to say that their parents had high expectations for them but limited contact with them. The parents themselves were not interviewed.
According to the American Journal of Psychiatry, surprisingly, the risk for bulimia was not related to social class, income, education, occupation, the occupation of parents, or even an outgoing or introverted personality. A woman’s childhood relationship with her mother, as she reported it, was not associated with bulimia, but neglect by her father was. Women with bulimia had lower self-esteem and more neurotic symptoms, and they were more likely to say they were not in control of their lives. They also had a slimmer ideal body image, and they dieted and exercised more. The risk factors for narrowly and broadly defined bulimia were similar (Kendler, 1991).
Women with broadly defined bulimia had high rates of phobias, alcoholism, anxiety disorders, anorexia nervosa, and panic attacks. Their lifetime rate of major depression was also high (50 percent), but bulimia had no special association with that common disorder. All other things being equal, a woman with a history of major depression was 2.2 times more likely to have suffered from bulimia as well. The corresponding odds ratio for phobias was 2.4, for alcoholism 3.2, and for anorexia nervosa 8.2. In most studies of patients treated for both bulimia and depression, bulimia is found to precede depression, but in this group of largely untreated people the depression had usually come first (Roth, 1996).
In some families of women with bulimia, the problem may be more serious than rigidity, over protectiveness, or inadequate nurturing. Child sexual abuse, an increasingly common explanation for psychiatric symptoms in women, has naturally been proposed as a cause of eating disorders. The connection has not been confirmed, and some recent studies raise serious doubts about it. Women with bulimia do not report more sexual abuse than an anxious and depressed woman in general.
The problem of bulimia is closely related to the problem of obesity, since almost all bulimic women either are or think they are overweight. According to a widely accepted theory, each person’s body weight has a biological set point that is strongly influenced by heredity and difficult to change. Studies in several countries have found that mothers and their biological daughters have a similar weight-height ratio, while the correlation between adoptive parents and adoptive children is low. According to the set point theory, metabolism during a diet shows to counteract the effect of reduced intake until it settles at a lower level consistent with the new weight. A person who continues the same diet will eventually regain weight until the set point is reached.
Many individuals with bulimia do not seek help until they reach their thirties or forties when their eating behavior is deeply ingrained and more difficult to change.
Bulimia is often treated more successfully than anorexia, partly because bulimic patients usually want to be treated. Most antidepressant drugs relieve the symptoms, usually more quickly than they relieve depression. Selective serotonin reuptake inhibitors (SSRIs) are probably most useful, because they have relatively few side effects and tend to cause weight loss rather than weight gain. In 1997, fluoxetine became the first drug specifically approved by the Food and Drug Administration (FDA) as a treatment for bulimia.
Roth, W.T., & Insel P.M. (1996). Core Concepts in Health. Toronto: Mayfield.
Kendler, K.S. (1991). The genetic epidemiology of bulimia nervosa. American Journal of Psychiatry, 148:1627-1637.
Mitchell, J.E. (1996). Bulimia Nervosa. West Virginia Health Page.