An eating disorder (ED) is a mental disorder defined by abnormal eating behaviors that adversely affect a person's physical or mental health. These behaviors may include eating too much food or too little food, as well as body image issues. Types of eating disorders include binge eating disorder, where the person suffering keeps eating large amounts in a short period of time typically while not being hungry, often leading to weight gain; anorexia nervosa, where the person has an intense fear of gaining weight, thus restricts food and/or overexercises to manage this fear; bulimia nervosa, where individuals eat a large quantity (binging) then try to rid themselves of the food (purging), in an attempt to not gain any weight; pica, where the patient eats non-food items; rumination syndrome, where the patient 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; 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. People often experience comorbidity between an eating disorder and OCD.
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.
