Study Tracks Prevalence of Eating Disorders

February 9, 2007 • Science Update

Results from a large-scale national survey suggest that binge-eating disorder is more prevalent than both anorexia nervosa and bulimia nervosa. The study, published in the February 1, 2007, issue of Biological Psychiatry, was based on data gleaned from the NIMH-funded National Comorbidity Survey Replication (NCS-R) a nationally representative survey conducted between February 2001 and December 2003.

James I. Hudson, MD, ScD of McLean Hospital and Harvard Medical School and colleagues analyzed data from 2,980 adults who were asked about eating disorders. They found that 0.9 percent of women and 0.3 percent of men reported having anorexia at some time in their lives, and 1.5 percent of women and 0.5 percent of men reported having bulimia. In contrast, 3.5 percent of women and 2 percent of men reported having binge-eating disorder at some point in their lives. The study also found that people with eating disorders, regardless of the type, often have coexisting mood, anxiety, impulse-control, or substance use disorders.

Anorexia nervosa is characterized by emaciation, a relentless pursuit of thinness and extremely disturbed eating behaviors, such as deliberate self-starvation. Bulimia nervosa is characterized by recurrent and frequent episodes of eating unusually large amounts of food (binging) during which a person feels a lack of control over the eating, followed by purging behavior such as vomiting, fasting, use of diuretics (water pills), or excessive exercise. Binge-eating disorder is characterized by recurrent binge-eating episodes during which a person feels a loss of control similar to bulimia. Unlike bulimia, however, binge-eating episodes are not followed by purging, excessive exercise or fasting.

Although more than 50 percent of those with eating disorders reported receiving treatment for emotional problems at some point in their lives, less than 45 percent sought treatment specific to their eating disorder. When they did seek treatment, they most commonly went to the general medical sector rather than specialized care.

Finally, study results suggest that anorexia may be a less chronic illness than either bulimia or binge-eating disorder. The average duration of anorexia was 1.7 years, while people with bulimia or binge-eating had their condition for about eight years each. Hudson and colleagues note that this discrepancy may reflect a reluctance or inability among people with chronic anorexia to participate in the study.

Overall, the study concluded that eating disorders often coexist with other disorders. Detection and treatment for eating disorders might be increased if providers more regularly asked patients about possible eating problems. They also noted that binge-eating disorder should be considered a public health concern because symptoms of the illness appear to be more prevalent than other eating disorders, and it is strongly associated with obesity.

Hudson JI, Hiripi E, Pope HG, Kessler RC. The Prevalence and Correlates of Eating Disorders in the National Comorbidity Survey Replication . Biological Psychiatry 2007; 61:348-358.