Wages, BMI, and Age

Previous research generally finds that obesity negatively affects wages for women and does not affect wages for men. But this literature has for the most part focused on young workers and has not examined whether the effect of obesity might change as people age. In this essay, I examine the effect of obesity -- and body mass more generally -- on wages across the age distribution, using conventional parametric and flexible semiparametric fixed effect models. The model results suggest two contributions to previous literature. First, the parametric results indicate that, in failing to stratify by age, the literature may overstate the effect of BMI and obesity on wages for women and almost certainly understates any negative association for men. Secondly, the semiparametric models indicate that the wage function isn't really changing as either men or women age: the differences that we observe in the linear specifications are almost all due to the change in the distribution of BMI, rather than a change in the effect of BMI itself on wages.