The pathogenesis of obesity is multi-factorial; both genetics and the environment influence the many variables that regulate body weight, metabolism, and eating behavior. The loss of control of eating behavior associated with obesity is analogous to the compulsive drug taking behavior observed in drug-addicted individuals. The American Society of Addiction Medicine first proposed the hypothesis of a food addiction over 10 years ago. Evidence from clinical observations and experimental research, in particular neuroimaging studies, provides substantial support for the relationship between binge-eating obesity, addiction, and the DA reward system.