Comparing Food Desert and Non-Food Desert Residents by Key Socio-Demographic Variables, Distance to supermarkets, Supermarket Type by Price, Diet Quality and Obesity in King County, Washington

Abstract

The causes of obesity are multi-factorial; however, decreased access to healthy and affordable foods has emerged as an important factor. Areas where access to healthy and affordable foods is limited are known as food deserts. Although the definition of food deserts has evolved since the term was coined in the early 1990s, it is currently defined by the USDA using distance and income as the main criteria and census tracts as the geographic unit. A new web-based tool called the USDA Food Desert Locator was developed in 2011 to identify food desert census tracts across the U.S. using the USDA definition. This study utilizes information from the USDA Food Desert Locator to enhance a secondary data analysis of the Seattle Obesity Study (SOS). The overall goal of this study is to describe and compare the socioeconomic status (SES) of participants enrolled in the Seattle Obesity Study (SOS), a large county based study of food cost, access and quality. This study will also analyze the effects of residing in a food desert on measures of diet quality and obesity measures such as body mass index (BMI) among SOS participants. This is a secondary data analysis of the SOS. Briefly, the SOS is a 2007 cross-sectional telephone survey that was modeled on the CDC's Behavioral Risk Factor Surveillance System (BRFSS). The data was collected within King County, Washington in 2007 and 2008. Data for 2,001 participants was collected. The SOS survey captured extensive data on food and eating, along with demographic factors and physical measures including height and weight. Food deserts were determined using the USDA Food Desert Locator tool. Seventeen census tracts were identified and used to filter SOS participants within King County, Washington. This study analyzed individual level data to ascertain relationships between food desert residence and SES, supermarket type by price, diet quality and obesity. Results show that residing in a food desert is not the key factor associated with obesity, but that SES as defined by income and education are. Solving issues surrounding access to healthy fruits and vegetables may not be as easy as previously thought. Building a new supermarket in food deserts may solve issues of access relating to distance, but it may not solve the socioeconomic challenges facing food desert residents.