An eating disorder is a mental disorder defined by abnormal eating behaviors that negatively affect a person's physical or mental health. Only one eating disorder can be diagnosed at a given time. Types of eating disorders include binge eating disorder, where the afflicted eats a large amount in a short period of time; anorexia nervosa, where the person afflicted has an intense fear of gaining weight and restricts food or overexercises to manage this fear; bulimia nervosa, where afflicted individuals eat a large quantity (binging) then try to rid themselves of the food (purging); pica, where the afflicted eats non-food items; rumination syndrome, where the afflicted regurgitates undigested or minimally digested food; avoidant/restrictive food intake disorder (ARFID), where people have a reduced or selective food intake due to some psychological reasons (see below); and a group of other specified feeding or eating disorders. Anxiety disorders, depression and substance abuse are common among people with eating disorders. These disorders do not include obesity.
The causes of eating disorders are not clear, although both biological and environmental factors appear to play a role. Cultural idealization of thinness is believed to contribute to some eating disorders. Individuals who have experienced sexual abuse are also more likely to develop eating disorders. Some disorders such as pica and rumination disorder occur more often in people with intellectual disabilities.
Treatment can be effective for many eating disorders. Treatment varies by disorder and may involve counseling, dietary advice, reducing excessive exercise, and the reduction of efforts to eliminate food. Medications may be used to help with some of the associated symptoms. Hospitalization may be needed in more serious cases. About 70% of people with anorexia and 50% of people with bulimia recover within five years. Recovery from binge eating disorder is less clear and estimated at 20% to 60%. Both anorexia and bulimia increase the risk of death.
Estimates of the prevalence of eating disorders vary widely, reflecting differences in gender, age, and culture as well as methods used for diagnosis and measurement. In the developed world, anorexia affects about 0.4% and bulimia affects about 1.3% of young women in a given year. Binge eating disorder affects about 1.6% of women and 0.8% of men in a given year. According to one analysis, the percent of women who will have anorexia at some point in their lives may be up to 4%, or up to 2% for bulimia and binge eating disorders. Rates of eating disorders appear to be lower in less developed countries. Anorexia and bulimia occur nearly ten times more often in females than males. The typical onset of eating disorders in late childhood to early adulthood. Rates of other eating disorders are not clear.
A 1984 international conference on the subject disclosed that the number of adolescents with anorexia nervosa and bulimia, eating disorders characterized by starvation or binge eating and purging, had increased dramatically in the past 15 years. In the USA, for example, a third of female high school and college students show tendencies toward anorexia or bulimia, or both.
Men who suffer from eating disorders have higher rates of depression, anxiety disorders and alcohol abuse than their peers. These men are also more likely to report problems in their marriage and feel dissatisfied with life in general. However, it is not clear whether these findings reflect factors that predispose a person to an eating disorder or are consequences of anorexia and bulimia.
In other findings, eating disorders appeared to be clinically similar in both sexes.
However, eating disorders and excessive dieting are 10 times more common in women than in men. Karen Carpenter, a famous American singer, died of heart strain due to anorexia nervosa, and in 1985 Jane Fonda, American actress, author, and activist, disclosed that she had been bulimic during her late teens and early twenties.