BEH collaborator Nico Berger and BEH member Gina Lovasi recently led a study on changes in the unhealthy retail food environment in New York City. The study found that the number of food outlets selling calorie-dense foods such as pizza and pastries dramatically increased between 1990 and 2010. Differences in trajectories were observed across neighborhoods: neighborhoods with a higher initial number of unhealthy food outlets in 1990 experienced a more rapid increase over time. Greater increase in unhealthy food outlets were observed in neighborhood with higher population size, lower income, and lower proportion of Black residents. Greater unhealthy food outlet increases were also noted in the context of neighborhood change suggestive of urbanization (increasing population density) or increasing purchasing power (increasing income).

This study used longitudinal data from the National Establishment Time-Series (NETS), a large historical dataset of retail businesses.  The number of retail outlets classified as selling “BMI-unhealthy” foods was counted every year at the census tract-level. BMI-unhealthy food outlets included convenience stores, “bodegas” or very small grocery stores, fast food restaurants, pizza restaurants, bakery or candy/confectionery stores, and meat markets.

Trajectories of changes were analyzed using Latent Class Growth Analysis in order to identify neighborhoods with similar patterns of changes.  The analyses identified five latent classes, which can be thought of as typologies of neighborhood trajectories for the availability of BMI-unhealthy food retail.  The figure below shows the count of BMI-unhealthy retail outlets per year for each of the five latent classes.

This study concludes that initiatives to reduce neighborhood exposure to unhealthy food should focus on disadvantaged neighborhoods in order to reduce environmental and health disparities. Attention should be given to the broader retail business context to ensure changes do not have the unintended consequence of increased health disparities.