According to the Diagnostic and statistical manual of mental disorders (DSM-5), eating disorders are "characterized by a persistent disturbance of eating or eating-related behavior that results in the altered consumption or absorption of food and that significantly impairs physical health or psychosocial functioning." 

Eating disorders include the following (DSM-V and ICD-10-CM classification included):

• Pica 307.52 (In children F98.3; in adults F50.8)
• Rumination Disorder 307.53 (F98.21)
• Avoidant/Restrictive Food Intake Disorder 307.59 (F50.8)
• Anorexia Nervosa 307.1 (F50.0_)
• Bulimia Nervosa 307.51 (F50.2)
• Binge-Eating Disorder 307.51 (F50.8)

According to the National Institute of Mental Health's "Eating Disorders Among Adults - Anorexia Nervosa," "Eating Disorders Among Adults - Binge Eating Disorder," and "Eating Disorders Among Adults - Bulimia Nervosa:"

• .6% of the U.S. population will experience anorexia in their lifetime
• The average age of onset for anorexia is 19 years old
• 2.8% of U.S. adults will experience binge eating disorder with the average age of onset being 25
• .6% of the U.S. population will experience bulimia in their lifetime
• The average age of onset for bulimia is 20 years old