Eating disorder

An eating disorder is a mental disorder defined by abnormal eating behaviors that adversely affect a person's physical or mental health.^[1] Types of eating disorders include binge eating disorder, where the patient eats a large amount in a short period of time; anorexia nervosa, where the person has an intense fear of gaining weight and restricts food or overexercises to manage this fear; bulimia nervosa, where individuals eat a large quantity (binging) then try to rid themselves of the food (purging); 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.^[1] Anxiety disorders, depression and substance abuse are common among people with eating disorders.^[2] These disorders do not include obesity.^[1] People often experience comorbidity between an eating disorder and OCD. It is estimated 20–60% of patients with an ED have a history of OCD.^[9]

The causes of eating disorders are not clear, although both biological and environmental factors appear to play a role.^[2][4] Cultural idealization of thinness is believed to contribute to some eating disorders.^[4] Individuals who have experienced sexual abuse are also more likely to develop eating disorders.^[7] Some disorders such as pica and rumination disorder occur more often in people with intellectual disabilities.^[1]

Treatment can be effective for many eating disorders.^[2] Treatment varies by disorder and may involve counseling, dietary advice, reducing excessive exercise, and the reduction of efforts to eliminate food.^[2] Medications may be used to help with some of the associated symptoms.^[2] Hospitalization may be needed in more serious cases.^[2] About 70% of people with anorexia and 50% of people with bulimia recover within five years.^[10] Only 10% of people with eating disorders receive treatment, and of those, approximately 80% do not receive the proper care. Many are sent home weeks earlier than the recommended stay and are not provided with the necessary treatment.^[11] Recovery from binge eating disorder is less clear and estimated at 20% to 60%.^[10] Both anorexia and bulimia increase the risk of death.^[10] When people experience comorbidity with an eating disorder and OCD, certain aspects of treatment can be negatively impacted. OCD can make it harder to recover from obsession over weight and shape, body dissatisfaction, and body checking.^[12] This is in part because ED cognitions serve a similar purpose to OCD obsessions and compulsions (e.g., safety behaviors as temporary relief from anxiety).^[13] Research shows OCD does not have an impact on the BMI of patients during treatment.^[12]

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.^[14][15][16] In the developed world, anorexia affects about 0.4% and bulimia affects about 1.3% of young women in a given year.^[1] Binge eating disorder affects about 1.6% of women and 0.8% of men in a given year.^[1] 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.^[10] Rates of eating disorders appear to be lower in less developed countries.^[17] Anorexia and bulimia occur nearly ten times more often in females than males.^[1] The typical onset of eating disorders is in late childhood to early adulthood.^[2] Rates of other eating disorders are not clear.^[1]