Food Swamps? the Effect of Imbalanced Food Environments on Obesity
*Names in bold indicate Presenter
Methods: Using secondary data from the USDA Food Environment Atlas, ordinary least squares (OLS) and IV regression models were employed to analyze cross-sectional associations between local food environments and the prevalence of obesity. The sample include 3,108 U.S. Counties. I used the number of highway exits per county as an instrument for food environments characterized as food swamps.
Results: I find even after controlling for food desert effects, food swamps have a positive, statistically significant effect on adult obesity rates. All seven food swamp measures indicated the same positive association, but reflected different magnitudes of the food swamp effect on obesity. Also, without adjusting for reverse causality using an IV approach, this effect would have been underestimated by naïve OLS estimates. The food swamp effect remains in counties with higher educational attainment and more income inequality. Finally, food swamps increase obesity by almost 9 percent in counties where more people drive to work.
Conclusions: Preliminary findings provide evidence for zoning strategies to simultaneously restrict access to unhealthy food outlets and incentivize healthy food retailers to locate in underserved neighborhoods. The results of this study suggest that zoning ordinances might establish quotas for the number of fast food restaurants or convenience stores in a municipality or target establishments that make unhealthy foods more convenient for drivers (i.e. drive-thrus).