Clinical implications for the treatment of obesity.

Combining Behavior and Biology This conference has underscored the magnitude and complexity of the obesity problem across the globe (1). Efforts to effectively prevent and treat obesity must be grounded in a precise understanding of etiology and pathophysiology. Although the fundamental energy imbalance is well known, the myriad of factors that affect that imbalance are less well understood (2). In addition, obese person are quite heterogeneous both behaviorally and biologically, making one size fits all treatments less likely to succeed in the long term. Given the complex and refractory nature of obesity, it is useful to employ treatment strategies that attempt to address both the biology and behavior of obesity. This conference has focused on the considerable science around the regulation of food intake, including the brain, the gut, and beyond (3–7). These systems are complex and, unfortunately, for weight reduction purposes, redundant. Therefore, efforts to trick the physiological system are likely to be subject to habituation, compensation, and/or adaptation. As Mela (7) suggests, consumers are eager for products that manage hunger, although it is less clear what is meant by hunger (8). It may be internally mediated by going long periods without eating or more externally driven by multiple triggers associated with eating (sight, smell, activities and emotions, places). Attempts to develop products or agents that modify the internal milieu are best complemented by behavioral strategies that seek to manage the multiple external prompts to eat more and move less. The remainder of this paper will describe the principles of behavior treatment and its efficacy. Behavioral Treatment Behavioral treatment is based largely on principles of classical conditioning, which posit that eating is often prompted by antecedent events (i.e., cues) that become strongly linked to food intake (9). Behavioral treatment, as described below, helps patients identify cues that trigger inappropriate eating (and activity) and learn new responses to them (10,11). Treatment also seeks to reinforce (or reward) the adoption of positive behaviors, while also reducing the aversiveness associated with some types of behavior change. In the last 20 years, cognitive therapy also has been incorporated in the behavioral treatment of obesity. The underlying assumption of cognitive therapy is that thoughts (or cognitions) directly affect feelings and behaviors (12). Negative thoughts frequently are associated with negative outcomes, as in the case of a male, who overeats, tells himself he has blown his diet, and then proceeds to eat triple the original amount because of feelings of disgust and despair. With cognitive therapy, patients learn to set realistic goals for weight and behavior change, to evaluate their success in modifying eating and activity habits, and to correct negative thoughts that occur when they do not meet their goals (11,13,14). Cognitive interventions for weight management are based on those developed for the treatments of depression and anxiety (15,16).