Race and gender differences in the cognitive effects of childhood overweight

The increase in the prevalence of overweight children (ages 6-13 years) in the United States over the past two decades is likely to result in adverse public health consequences. We use data from the children of the National Longitudinal Survey of Youth 1979 cohort to investigate an additional consequence of childhood overweight - its effect on relative cognitive development. To control for unobserved heterogeneity, we estimate individual (child) fixed effect (FE) models and instrumental variable (IV) models. Although recent research suggests that there is a negligible effect of childhood overweight on cognitive ability, our results demonstrate that the effects are uncovered when examining the relationship separately by race. In particular, we find that overweight white boys have math and reading scores approximately an SD lower than the mean. Overweight white girls have lower math scores whereas overweight black boys and girls have lower reading scores. Our results suggest that in addition to well-documented health consequences, overweight children may also be at risk in terms of experiencing adverse education outcomes, which could lead to lower future wages.