Childhood obesity and air pollution: Evidence from China

We provide causal estimates of the effect of fine particulate matter pollution on childhood overweight and obesity. The estimate is based on quasiexperimental variation in PM2.5 levels resulting from China's Huai River Policy. The policy offered free or heavily subsidized coal for indoor heating during the winter to cities located north of the Huai River, while cities located south of the river did not receive such benefits. Using data from the 2018 China Household Income Project in a regression discontinuity design, we find that the Huai River policy increased overweight and obesity among Chinese children. Results from a two-stage least squares model estimate that a 10 mu g/m 3 increase in PM2.5 increases the fraction of children classified as obese by about five percentage points.