Association for Public Policy Analysis & Management

Diet-related illnesses such as obesity and diabetes may be more pronounced in some poor and rural American communities because there is limited access to affordable and nutritious foods. A primary concern is that some areas do not have access to supermarkets or other food retailers that offer the variety of foods needed for a healthy diet (for example, fresh fruits and vegetables, whole grains, fresh dairy and meat products). Instead, individuals in these areas may be more reliant on food retailers or fast food restaurants that only offer more limited varieties of foods. It is hypothesized that the relative lack of access to supermarkets and easier access to fast and convenience foods may be linked to poor diet and, ultimately, to obesity and other diet-related diseases.

Many early cross-sectional studies found an association between the level of access to healthy food and diet and health outcomes. More recent studies have used longitudinal data to tease out the extent to which the food environment contributes to differences in the healthfulness of food purchases, diet and obesity and the extent to which other factors, such as food prices and preferences explain differences in these outcomes. While advancing the literature, these studies often consider only concurrent effects of the food environment on outcomes and do not examine how longer-term exposure may accumulate and impact the longer term diet-related outcomes. Further, many of these studies use data on small segments of the U.S. population (e.g. longitudinal studies of schoolchildren or youth in a single state). Our work builds upon these studies by examining how exposure to poor food environments impacts the onset of chronic diet-related conditions, such as obesity, diabetes, high blood pressure and heart disease. Our contribution is to use a long-term national longitudinal study, the Panel Study of Income Dynamics (PSID), and hazard analysis and to explicitly examine how the amount of time spent in a poor food environment impacts the onset of chronic diet-related conditions.

We match the PSID data to longitudinal data on the location of food retailers from the Food and Nutrition Service of the U.S. Department of Agriculture’s Store Tracking and Redemption System (STARS), which collects basic information on stores authorized to accept benefits from the Supplemental Nutrition Assistance Program (SNAP). We use information on store types and geocodes to measure access to a healthy retailer for the census tract in which PSID respondents live. Limiting our analysis to PSID rounds that coincide with our food environment data, we use data from 1990-2013 on a sample of working age adults age 18 to 55 and apply a hazard model analysis to estimate the effects of exposure to poor food environments on the onset of each diet-related condition. We also use the food security questions that were asked between 1999 and 2003 to examine if there is a relationship between a household’s food environment and food security status and also whether past periods of food insecurity intensify the relationship between a household’s food environment and individual health outcomes.