When does weight matter most?

Past empirical work establishes a wage penalty from being overweight. In this paper, I exploit variation in an individual's weight over time to determine the age when weight has the largest impact on labor market outcomes. For white men, controlling for weight at younger ages does not eliminate the effect of older adult weight on wage: being overweight as a young adult only adds an additional penalty to adult wages. However, for white women, what they weigh in their early twenties solely determines the existence of an adult wage penalty. The female early-twenties weight penalty has a persistent effect on wages, and differences in marital characteristics, occupation status, or education cannot explain it. It also is not a proxy for intergenerational unobservables.