Animal models of sugar and fat bingeing: relationship to food addiction and increased body weight.

Binge eating is a behavior that occurs in some eating disorders, as well as in obesity and in nonclinical populations. Both sugars and fats are readily consumed by human beings and are common components of binges. This chapter describes animal models of sugar and fat bingeing, which allow for a detailed analysis of these behaviors and their concomitant physiological effects. The model of sugar bingeing has been used successfully to elicit behavioral and neurochemical signs of dependence in rats; e.g., indices of opiate-like withdrawal, increased intake after abstinence, cross-sensitization with drugs of abuse, and the repeated release of dopamine in the nucleus accumbens following repeated bingeing. Studies using the model of fat bingeing suggest that it can produce some, but not all, of the signs of dependence that are seen with sugar binge eating, as well as increase body weight, potentially leading to obesity.