“As an undergraduate student in psychology, I was taught that multiple personalities were a very rare and bizarre disorder. That is all that I was taught on ... It soon became apparent that what I had been taught was simply not true. Not only was I meeting people with multiplicity; these individuals entering my life were normal human beings with much to offer. They were simply people who had endured more than their share of pain in this life and were struggling to make sense of it.”
― Deborah Bray Haddock, The Dissociative Identity Disorder Sourcebook
Dissociative Identity Disorder (DID) is frequently comorbid with feeding and eating disorders, known previously simply as eating disorders.
Feeding and eating disorders include pica (specify if in remission; can be in either children or adults), rumination disorder (specify if in remission), avoidant/restrictive food intake disorder (specify if in remission), anorexia nervosa (specify if in partial remission or in full remission; mild, moderate, severe, extreme; restricting type or binge-eating/purging type), bulimia nervosa (specify if in partial remission or in full remission; mild, moderate, severe, extreme), binge-eating disorder (specify if in partial remission or in full remission; mild, moderate, severe, extreme), other specified feeding or eating disorder, and unspecified feeding or eating disorder.
Feeding and 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." The diagnoses of rumination disorder, avoidant/restrictive food intake disorder, anorexia nervosa, bulimia nervosa, and binge-eating disorder are mutually exclusive, but pica can be diagnosed alongside any of the other feeding and eating disorders.
Pica involves the persistent and developmentally inappropriate eating of nonnutritive, nonfood substances. If sufficiently severe, this may be diagnosed alongside an intellectual disability, autism spectrum disorder, schizophrenia, or medical condition in which it might normally be associated.
Rumination disorder involves repeatedly regurgitating food that may be re-chewed, re-swallowed, or spit out. This is not due to gastrointestinal or other medical conditions or to another feeding and eating disorder. It must sufficiently severe to be diagnosed alongside an intellectual or neurodevelopmental disability.
Avoidant/restrictive food intake disorder regards an eating or feeding disturbance (such as an apparent lack of interest in eating or food, avoidance of food based on its sensory characteristics, or concern about consequences of eating) "as manifested by persistent failure to meet appropriate nutritional and/or energy needs associated with" significant weight loss, nutritional deficiency, dependence on enteral feeding or oral nutritional supplements, or marked interference with psychosocial functioning. This disorder is not due to a lack of available food or a cultural practice, and it is not associated with another feeding and eating disorder. It is not due to another medical condition or mental disorder, though it may be comorbid with another medical condition or mental disorder if it is more severe than would be expected for those conditions.
Anorexia nervosa pertains to a restriction of energy intake that leads to a significantly low body weight. It is associated with an intense fear of gaining weight or behaviors that prevent weight gain as well as with a disturbance in how one perceives one's body weight or shape, an emphasis on body weight or shape in self evaluation, or a lack of recognition of the seriousness of the condition. The restricting type accomplishes weight loss mainly through dieting, fasting, or excessive exercise while the binge-eating/purging type accomplishes weight loss mainly through binge eating or purging behavior (such as "self-induced vomiting or the misuse of laxatives, diuretics, or enemas)."
Bulimia nervosa is characterized by periods of binge eating (eating large amounts of food without feeling that one has control over this eating) and restricting or purging behaviors such as those seen in anorexia nervosa. "Self-evaluation is unduly influenced by body shape and weight." It is different from the binge-eating/purging type of anorexia nervosa according to weight.
Binge-eating disorder is characterized by recurrent episodes of binge eating as found in bulimia nervosa in addition to 3 or more of the following: eating more rapidly than usual, until uncomfortably full, when not feeling physically hungry, or when alone because of embarrassment over how much one is eating, or feeling disgusted with oneself, depressed, or very guilty after eating.
All information taken from the DSM-5.
American Psychiatric Association. (2013). Feeding and Eating Disorders. In Diagnostic and statistical manual of mental disorders (5th ed.). http://dx.doi.org/10.1176/appi.books.9780890425596.dsm10