Eating disorders are a group of diseases in which abnormal eating behavior occurs under the interaction of psychological factors, social factors and specific cultural pressures, specifically including: 1. Anorexia nervosa: the patient consciously abstains from eating, resulting in a weight significantly lower than the normal standard; 2. Bulimia nervosa: with recurrent, irresistible desire to eat and overeating or binge eating behavior, but after eating, and fear of gaining weight and Take various methods to reduce weight, so that the patient’s weight change does not necessarily increase significantly; 3, neurotic vomiting: patients appear after eating spontaneously or deliberately induced repeated vomiting, does not affect the next meal.