Intersection of neighborhood segregation, poverty, and urbanicity on the availability of food stores in the United States

Background: The availability of food stores is a potential determinant of the quality of foods consumed by different racial/ethnic groups. This, in turn, may account for significant racial disparities seen in obesity. Neighborhood racial residential segregation, poverty, and urbanicity have been demonstrated to independently affect food store availability, but the interactions among them have not been well studied. Purpose: This study examines availability of supermarkets, grocery stores, and convenience stores in US census tracts according to neighborhood racial/ethnic residential segregation, poverty, and urbanicity. Methods: Cross-sectional area level data from the 2000 US Census and food store data from InfoUSA 2001 were combined to run multivariate negative binomial regression models. Results: In the nationwide and urban samples, all racial/ethnic groups had a decrease in supermarket availability and an increase in grocery and convenience store availability as poverty increased. At equal levels of poverty, black tracts had the fewest supermarkets, white tracts had the most, and integrated tracts were intermediate. Hispanic tracts had the most grocery stores at all levels of poverty. In the rural sample, neither racial composition nor level of poverty was predictive of supermarket availability in rural tracts and high poverty black and integrated tracts had more supermarkets than similar high poverty urban tracts. Conclusions: There are significant interactions among neighborhood racial/ethnic composition, poverty level, and urbanicity that influence the availability of supermarkets, grocery stores, and convenience stores in the US. Understanding these interactions will improve the design and targeting of interventions to increase access to high quality foods.