Obesity and anorexia

Eating disorders frequently develop during adolescence or early adulthood. Much attention is paid to anorexia nervosa (AN) and bulimia nervosa (BN), both eating disorders that are more likely to be found in females than in males (Hoek, 2006). As of now, it is estimated that AN and BN affect about 3% of young women with nearly twice this number having eating problems that do not reach diagnostic thresholds. Consequences of these eating disorders can be devastating and far-reaching. For example, individuals suffering from AN or BN frequently go into remission, and about 5 to 10% of them die due to complications such as heart and kidney failure (Casiero and Frishman, 2006; Hoek, 2006). According to the DSM-IV criteria, AN is characterized by self-starvation, and a refusal to maintain a minimally normal body weight. Bulimia nervosa is characterized by repeated binge-eating episodes, which are usually followed by self-induced vomiting, intake of laxatives and diuretics, or other medications aimed at induction of weight loss. Eating disorders are frequently found to occur with other psychiatric disorders such as depression, addiction, and anxiety. Furthermore, individuals suffering from AN and BN often have a disturbed perception of body shape and weight, and judge themselves as too fat (Ruuska et al., 2005). Another frequently mentioned eating disorder on the other side of the spectrum is binge eating disorder (BED). According to the DSM-IV criteria, BED subjects have binges at least twice a week over a period of six months or more. Each binge is characterized by ingesting a large amount of food at a high feeding rate, and continues far beyond the normal sensation of satiety. Binge eating disorder is commonly associated with obesity, and - as opposed to AN and BN subjects - BED obese individuals are generally quite aware of their fat state (Gromel et al., 2000). In fact, they frequently feel stigmatized as such (Puhl et al., 2007). Since obesity is considered a general medical condition according to the International Classification of Diseases (ICD), and no consistent psychological syndrome is associated with it, it has not been classified in the DSM-IV. However, reports nevertheless suggest that obese individuals already at adolescence are frequently depressed according to the DSM-IV criteria (McElroy et al., 2004; Sjoberg et al., 2005).