The prevalence of obesity among both adults and children in the U.S. has risen to all time highs in the past two decades. We propose that an increase in the marginal rate of time preference has contributed to increasing obesity. More people are consuming more calories than they expend because they have become less willing to trade current pleasure for potential future health benefits. Accordingly, this paper explores the association between body mass index (BMI) and time preference. We use the National Longitudinal Survey of Youth (NLSY79) to test our hypothesis that time preference and BMI are positively related. We find some evidence that there is such a positive association among black and Hispanic men and black women.