Wealthier individuals engage in healthier behavior. This paper seeks to explain this phenomenon by developing a theory of health behavior, and exploiting both lottery winnings and inheritances to test the theory. We distinguish between the direct monetary cost and the indirect health cost (value of health lost) of unhealthyconsumption. The health cost increases with wealth and the degree of unhealthiness, leading wealthier individuals to consume more healthy and moderately unhealthy, but fewer severely unhealthy goods. The empirical evidence presented suggests that differences in health costs may indeed provide an explanation for behavioraldifferences, and ultimately health outcomes, between wealth groups.