The rise in obesity in the United States may slow or even reverse the long-term trend of increasing life expectancy. Like many risk factors for disease, obesity results from behavior and shows a social gradient. Especially among women, obesity is more common among lower-income individuals, those with less education, and some ethnic/racial minorities. This article examines the underlying assumptions and implications for policy and the interventions of the two predominant models used to explain the causes of obesity and also suggests a synthesis that avoids "blaming the victim" while acknowledging the role of individuals' health behaviors in weight maintenance. (1) The medical model focuses primarily on treatment, addressing individuals' personal behaviors as the cause of their obesity. An underlying assumption is that as independent agents, individuals make informed choices. Interventions are providing information and motivating individuals to modify their behaviors. (2) The public health model concentrates more on prevention and sees the roots of obesity in an obesogenic environment awash in influences that lead individuals to engage in health-damaging behaviors. Interventions are modifying environmental forces through social policies. (3) There is a tension between empowering individuals to manage their weight through diet and exercise and blaming them for failure to do so. Patterns of obesity by race/ethnicity and socioeconomic status highlight this tension. (4) Environments differ in their health-promoting resources; for example, poorer communities have fewer supermarkets, more fast-food outlets, and fewer accessible and safe recreational opportunities. A social justice perspective facilitates a synthesis of both models. This article proposes the concept of "behavioral justice" to convey the principle that individuals are responsible for engaging in health-promoting behaviors but should be held accountable only when they have adequate resources to do so. This perspective maintains both individuals' control and accountability for behaviors and society's responsibility to provide health-promoting environments.
