The Psychology of Binge Eating
Binge eating is found in a range of eating disorders (bulimia nervosa, binge eating disorder, anorexia nervosa of the binge–purge subtype, atypical cases; see Chapters 28 and 30 for a discussion of the classification of eating disorders), but it is also found widely in the nonclinical female population. It is important to consider issues of definition. Objective binge eating has two components—the consumption of a large amount of food over a relatively short period of time and the sensation of loss of control during that ingestion. These components are not always linked. Many patients describe subjective “binges,” which involve eating relatively small amounts of food and where loss of control is the distressing component. Others have behaviors that have been described as “grazing” (eating a large amount but over a long period of time, and with no perceived loss of control). The present review focuses on objective binges as the unit of analysis, since such eating creates the greatest level of distress and physical damage. Objective binges are also the best understood of the overeating phenomena.
In order to explain the behaviors that contribute to the onset and maintenance of binge eating, it is necessary to understand the interlinking behavioral, cognitive, affective, and interpersonal systems. The most comprehensive framework for understanding these factors from a psychological perspective is functional analysis—the explanation of behaviors in the context of their antecedents, consequences, and environmental setting. While such an approach is independent of theory, it most closely relates to a cognitive-behavioral analysis. This conclusion follows from the fact that cognitive-behavioral psychology has developed as an explanatory theory (generating models and predictions that are capable of being disproved), whereas other theoretical stances tend to be descriptive (involving post hoc rationalization of behavioral manifestations). At one end of the spectrum, cognitive-behavioral models are supported by evidence from a range of naturalistic, correlational, and experimental studies derived from theory; at the other, they are supported by impressive evidence from trials of cognitive-behavioral therapies. Finally, the cognitive-behavioral approach to understanding eating disorders is able to explain the route of effect of other influences on bulimic behaviors (e.g., social factors, trauma history).