Eating disorders are complex psychiatric syndromes in which cognitive distortions related to food and body weight and disturbed eating patterns can lead to significant and potentially life threatening medical and nutrition complications.1 The three types of eating disorders are: anorexia nervosa (AN), bulimia nervosa (BN) and eating disorder not otherwisespecified (EDNOS).2 Anorexia Nervosa • Anorexia nervosa is characterized by a denial of hunger and intentional restriction of energy and nutrient intake to a level inadequate to maintain health and normal weight (e.g., 600-900 calories/day).3 (See Table 1.) • • Intensive exercise and/or purging by means of self-induced vomiting, laxative abuse, diuretics, or enemas may also be used to promoteweight loss.3 Extreme body dissatisfaction, a delusion of being fat, an obsession with being thinner, and an intense fear of gaining weight persist regardless of the amount of weight lost.4
TABLE 1 Diagnostic Criteria for Anorexia Nervosa Refusal to maintain body weight at or above a minimally normal weight for age and height (e.g., weight loss leading to maintenance of body weight less than 85% ofthat expected; or failure to make expected weight gain during period of growth, leading to body weight less than 85% of that expected). Intense fear of gaining weight or becoming fat, even though underweight. 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 bodyweight. In postmenarcheal 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.)
Restricting Type: During the current episode of anorexia nervosa, the person has not regularly engaged in binge-eating or purging behavior (i.e.,self-induced vomiting or the misuse of laxatives, diuretics, or enemas). Binge-Eating/Purging Type: During the current episode of anorexia nervosa, the person has regularly engaged in binge-eating or purging behaviors (i.e., self-induced vomiting or the misuse of laxatives, diuretics, or enemas).
Reprinted with permission from the Diagnostic and statistical manual of mental disorders, 4th ed, TextRevision, Copyright 2000. American Psyciatric Association.
Stang J, Story M (eds) Guidelines for Adolescent Nutrition Services (2005) http://www.epi.umn.edu/let/pubs/adol_book.shtm
GUIDELINES FOR ADOLESCENT NUTRITION SERVICES
Bulimia Nervosa • Bulimia nervosa is associated with chaotic eating behaviors. Binge eating is followed by purging, fasting, and/or intensive exercise inan attempt to compensate for the excessive calories ingested.2 (See Table 2.) • Although commonly used in an attempt to purge all calories from the body following a binge, purging is ineffective. Approximately 1200 calories are retained after binging and vomiting, regardless of the amount eaten. Laxative use results primarily in fluid loss from the large intestine. The loss of ingested caloriesand nutrients, which are absorbed mainly by the small intestines, is minimal (approximately 10%).1,5 Binge eating is often triggered by negative mood, psychosocial stress, or severe hunger resulting from restricted eating or excessive exercise that occurs between binges.6 Large quantities of food, frequently high in carbohydrate or sugar, are consumed (approximately 3400-4800 calories per episode).Intake usually occurs rapidly and in secrecy, until extreme fullness. The binge may be planned or unplanned, but is associated with a loss of control over eating.2,5 Individuals with bulimia nervosa may be overweight, slightly underweight, or of normal weight, and often experience rapid weight fluctuations. Depression, anxiety disorders, substance abuse, self-mutilation, and/or extreme body...