The distributional effect of education on body mass

We investigate the effect of education on mid-life obesity, with particular attention to potential heterogeneity across the Body Mass Index (BMI) distribution. Applying quantile regression methods to British men and women, we first find that childhood and parental BMI are critical determinants of obesity in middle age. We then establish that even when controlling for various weight-related factors in childhood and a potential endogeneity bias, a higher education level reduces the probability of being obese in middle age. We show that this education effect is obtained by a compression of the distribution of BMI (kg/m2) and a shifting of its center leftward toward a more healthy BMI range. We further show that income and physical activity are important channels of the education effect, and the significant effect of education at the upper quantile of the BMI distribution is neither a disguised income effect nor a healthy behavior effect.