Characterizing the dynamic nature of SNAP food environments in the United States

Households participating in the Supplemental Nutrition Assistance Program (SNAP) are only able to redeem benefits approved food retailers. We focus our attention on food retailers approved to accept SNAP benefits over a 25-year period (1996-2020) to assess changes in the food retail environment for these shoppers. Using the USDA Historical SNAP Retailer Database, we calculate multiple food environment measures for each year in the study period, summarized at the 2010 Census tract level. Joined with county-level data from the 2008-2012 American Community Survey, we evaluate relationships between these measures and socioeconomic characteristics in linear mixed-effects models, including interaction terms to consider how effects vary across levels of population density, race and ethnicity, and SNAP participation rates. As an exploratory aim, we also applied a similar modeling approach to document the expansion of dollar store retailers. We describe an overall expansion of SNAP retailer access, with significant differences by tract sociodemographic characteristics. These findings illustrate the utility of multi-component, dynamic considerations of food retail environments, especially in the context of SNAP policy.