Eating disorder: It is a group of mental disorders mainly based on abnormal eating behavior, mainly including anorexia nervosa, bulimia nervosa and vomiting nervosa. 1.Anorexia nervosa: It is a kind of abnormal eating behavior mostly seen in adolescent females, characterized by deliberate restriction of diet, so that the weight drops to significantly lower than the normal standard, for which excessive exercise, induced vomiting, diarrhea and other methods are used to reduce weight. 2, bulimia nervosa: is a kind of eating disorder, characterized by recurrent and irresistible desire to eat and overeating behavior, the patient has the fear of gaining weight, often take methods such as induced vomiting, diarrhea, fasting to eliminate the extreme measures of overeating caused by fat. 3, neurotic vomiting: is a group of mental disorders characterized by spontaneous or intentionally induced repeated vomiting, vomit for the things just eaten. Not accompanied by other obvious symptoms, vomiting is often related to psychosocial factors, no basis for organic lesions, there can be fear of gaining weight and the idea of weight loss, but no significant weight loss.