Dysfunctional eating in the eating disorders

Patients diagnosed with anorexia or bulimia nervosa present a complex nutri tional picture to clinicians. The principal symptoms of both eating disorde rs center on a pathologic fear of being or becoming fat. The pursuit of thi nness in anorexia and bulimia nervosa drives a range of behaviors from rest rained eating to self-starvation and may even be at the root of binge eatin g, and certainly purging. Chronic food restriction coupled with episodes of binge eating or purging contribute to the appetite desynchrony found in th e eating disorders.(35) When patients with eating disorders are followed up using dietary records k ept at home and monitored by a clinician, or in a laboratory setting and ob served by researchers, a variety of pathologic features of eating and appet ite regulation emerge. These features are apparent at different levels of a nalysis from the microstructure of eating within a single meal episode(21) to severe deficits or excesses in the overall diet of the individual.(5) Th ey also incorporate several psychological features, including dichotomous c ategorization of foods (good or bad, allowed or forbidden), negative affect during eating, pathologic fear of eating particular foods, and ambivalent attitudes about foods. Most of the studies of eating behavior have been conducted with patients wh o are seeking treatment or have just entered treatment. Studies of eating p atterns and food intake in patients during and following treatment indicate that, although there is some normalization of eating behavior, some aberra nt eating patterns persist.(2,) (66) Few studies have directly evaluated in terventions to "normalize" eating. Part of the problem in the treatment of anorexia or bulimia nervosa is identifying and characterizing the core feat ures of abnormal eating patterns. It seems self-evident that normative eati ng patterns will not be acquired unless specifically targeted in therapeuti c management, but understanding whether patients "can't eat" or "won't eat" is crucial to the development of these treatment strategies. It could be t rue that, for the anorexic patient, appropriate nutritional management and achieving normal weight will be sufficient to correct problematic eating, a nd that, for the bulimic patient, abstinence from binge eating and purging will result in normal eating. But what if the appetite regulation system is compromised in anorexia or bulimia nervosa beyond the eating abnormality e xhibited in long-term self-starvation, binge eating, and purging? There are significant implications for treatment if problems in appetite regulation are not limited to the most extreme behaviors, such as stringent dietary re striction or binge eating. If eating abnormality is distributed across the appetite system, including aberrant patterns of eating, inadequate food cho ices, disturbance in hunger, and satiety perception, then the clinician's t ask is to address all aspects of eating, appetite, food selection, and nutr ition. This article explores fundamental questions about the nature of eati ng problems experienced in the eating disorders and considers implications for treating identifiable components of eating abnormalities.