Geographic accessibility of food outlets not associated with body mass index change among veterans, 2009-14

In recent years, various levels of government in the United States have adopted or discussed subsidies, tax breaks, zoning laws, and other public policies that promote geographic access to healthy food. However, there is little evidence from large-scale longitudinal or quasi-experimental research to suggest that the local mix of food outlets actually affects body mass index (BMI). We used a longitudinal design to examine whether the proximity of food outlets, by type, was associated with BMI changes between 2009 and 2014 among 1.7 million veterans in 382 metropolitan areas. We found no evidence that either absolute or relative geographic accessibility of supermarkets, fast-food restaurants, or mass merchandisers was associated with changes in an individual's BMI over time. While policies that alter only geographic access to food outlets may promote equitable access to healthy food and improve nutrition, our findings suggest they will do little to combat obesity in adults.