Dynamic urban food environments a temporal analysis of access to healthy foods.

BACKGROUND Low-income, urban populations' limited access to healthy foods is often pointed to as a key barrier to improving nutrition. Although much has been written on identifying urban "food deserts," little has been done to examine how the food environment changes over the course of 1 year. PURPOSE This study was designed to dynamically describe the urban food environment as a means to identify when at-risk neighborhoods are without access to healthy food. METHODS Demographic and road data of Buffalo NY from the 2000 U.S. Census, a 2010 listing of city supermarkets, and 2011 government records of the time and location of urban farmers' markets are mapped. Road network distances from block groups to supermarkets and farmers' markets are calculated. A computer simulation, written in 2011, examines the market closest to each block group for 52 weeks. RESULTS The average distance to markets with produce from block groups with poverty levels in the top 10th percentile is greater than that across all block groups during winter and spring months. However, during the farmers' market season, the same impoverished block groups are on average closer to markets when compared to all block groups. CONCLUSIONS Including the temporal dimension in an analysis of healthy food access generates a more complex picture of urban food-desert locations. The implications are that spatiotemporal factors should be used to inform appropriate interventions for creating an equitable food environment.