Eating too much or too little is not necessarily an eating disorder. Clinicians and psychiatrists use diagnostic tools to decide if treatment is needed.
Eating Disorders Diagnostic Tools
In U.S., when diagnosing psychiatric illness, clinicians and psychiatrists usually use a handbook called Diagnostic and Statistical Manual of Mental Disorders (DSM). The DSM serves as the principal authority for psychiatric diagnoses. Treatment recommendations, as well as payment by health care providers, are often determined by DSM classifications.
Published by the American Psychiatric Association (APA), the DSM covers all categories of mental health disorders for both adults and children. It contains descriptions, symptoms, and other criteria necessary for diagnosing mental health disorders.
The DSM provides diagnostic criteria and codes for about 20 types of disorders, such as neurodevelopmental disorders, bipolar and related disorders, depressive disorders, anxiety disorders, trauma- and stressor-related disorders, dissociative disorders, etc.
Eating disorders fall under the “feeding and eating disorders” category in the DSM.
An alternative diagnostic handbook widely used in Europe and other parts of the world is the International Classification of Diseases (ICD), which is produced by the World Health Organization (WHO). The ICD has a broader scope than the DSM, covering overall health as well as mental health; chapter 5 of the ICD specifically covers mental and behavioral disorders.
Three Types of Eating Disorder
When using the diagnostic tools to assess eating disorders, clinicians need to decide what type of eating disorder a patient is experiencing. Common eating disorders include binge eating disorder, bulimia nervosa, and, less common but very serious, anorexia nervosa.
Binge eating disorder is characterized by recurrent binge eating episodes during which a person feels a loss of control and marked distress over his or her eating. People with binge eating disorder often are overweight or obese.
Bulimia nervosa is characterized by binge eating (eating large amounts of food in a short time, along with the sense of a loss of control) followed by a type of behavior that compensates for the binge, such as purging (e.g., vomiting, excessive use of laxatives, or diuretics), fasting, and/or excessive exercise.
Anorexia nervosa is characterized by a significant and persistent reduction in food intake leading to extremely low body weight in the context of age, sex, and physical health; a relentless pursuit of thinness; a distortion of body image and intense fear of gaining weight; and extremely disturbed eating behavior.
Eating Disorders Diagnostic Criteria
In a 2007 eating disorders research report, researchers provided a DSM-based assessment tool that they developed to aid the diagnosis of eating disorders:
A. A refusal to maintain body weight at or above a minimally normal weight for age and height (e.g. weight loss leading to a maintenance of body weight less than 85% of that expected; or failure to make expected weight gain during period of growth, leading to body weight less than 85% of that expected).
B. Intense fear of gaining weight or becoming fat, even though underweight.
C. Disturbance in the way in which one's body weight or shape is experienced, undue influence of body weight or shape on self-evaluation, or denial of the seriousness of the current low body weight.
D. In postmenarchal females, amenorrhea, i.e., the absence of at least three consecutive menstrual cycles. (A woman is considered to have amenorrhea if her periods occur only following hormone, e.g., estrogen, administration.)
A. Recurrent episodes of binge eating. An episode of binge eating is characterized by both of the following:
eating, in a discrete period of time (e.g., within any 2-hour period), an amount of food that is definitely larger than most people would eat during a similar period of time and under similar circumstances
a sense of lack of control over eating during the episode (e.g. a feeling that one cannot stop eating or control what or how much one is eating)
B. Recurrent inappropriate compensatory behavior in order to prevent weight gain, such as self-induced vomiting; misuse of laxatives, diuretics, enemas or other medications; fasting; or excessive exercise.
C. The binge eating and inappropriate compensatory behaviors both occur, on average, at least twice a week for 3 months.
D. Self-evaluation is unduly influenced by body shape and weight.
E. The disturbance does not occur exclusively during episodes of Anorexia Nervosa.
Binge Eating Disorder
A. Same as criterion A for bulimia nervosa (see above)
B. Binge eating episodes are associated with three or more of the following:
Eating much more rapidly than normal
Eating until feeling uncomfortably full
Eating large amounts of food when not physically hungry
Eating alone because of being embarrassed by how much one is eating
Feeling disgusted with oneself, depressed, or very guilty after overeating
C. Marked distress regarding binge eating is present
Hudson, James I., et al. “The Prevalence and Correlates of Eating Disorders in the National Comorbidity Survey Replication.” Biological Psychiatry, vol. 61, 2007, pp. 348–358.