Junk Food in Schools and Childhood Obesity Much Ado About Nothing?

There is a growing belief among policymakers and the general public that competitive foods in schools are a significant contributor to the childhood obesity epidemic. Numerous policy initiatives are underway at the local, state and federal level to regulate the availability of competitive foods in schools. However, the existing empirical evidence motivating these efforts is limited and rarely addresses the potential endogeneity of the school food environment. In this paper, we estimate the causal effect of competitive food availability on children’s body mass index (BMI) and other foodand school-related outcomes using an instrumental variables approach on a national sample of children. We find that competitive food availability generates in-school purchases of junk foods, but contrary to common concerns, there is no significant effect on children’s BMI. Nor do we observe significant changes in overall consumption of healthy and unhealthy foods, and in physical activity. Finally, our results find no support for broader effects of junk foods in school on social/behavioral and academic outcomes. *Corresponding author, RAND Corporation, 1776 Main Street, P.O. Box 2138, Santa Monica, CA 90407, Email: [email protected] This research was funded by grants from the Robert Wood Johnson Foundation’s Healthy Eating Research Program, NIH R01 HD057193, the Bing Center for Health Economics at RAND, and the RAND Labor and Population Program. All opinions are those of the authors and do not represent opinions of the funding agencies. We are grateful to Darius Lakdawalla, Neeraj Sood, Roland Sturm for their helpful comments, and to Carlos Dobkin and Eric Meijer for helpful discussions. We are also grateful to Le Wang for sharing his STATA code to estimate quantile regression instrumental variables models. All remaining errors are our own.