Kansas State researchers studied the availability of food stores for low-income women in Kansas to see whether there was a link to obesity. The findings showed that limited availability of grocery stores did not contribute to an increased risk of obesity in metropolitan or rural areas, but it was associated with an increased risk of obesity in micropolitan areas in Kansas, defined as cities with fewer than 40,000 people.
“This study was one of the first to look at supermarket availability across the urban-rural continuum, and the findings suggest that policies to increase healthful food availability may need to differ depending on urban influence,” David Dzewaltowski, Kansas State professor and department head of kinesiology, said in a news release.
Dzewaltowski and Paula Ford, assistant professor of public health sciences at the University of Texas at El Paso, published the study in the January issue of Obesity.
Dzewaltowski said most studies that have investigated links between food environments and obesity have relied upon census tracts or ZIP codes for analysis. However, this can lead to faulty results. The Kansas State study used a statewide, geographically referenced dataset of Kansans participating in the Special Supplemental Nutrition Program for Women, Infants and Children from October 2004 to December 2006.
“Previous research assumes that most people shop within their own census tract or ZIP code. However, other studies have found that most people shop outside of their census tract. By examining the number of stores within a 1- to 3-mile radius of these women’s homes, we were able to get a more accurate and realistic assessment of supermarket availability,” Ford said. “The study included only socioeconomically disadvantaged women because they are at greater risk of obesity than are wealthier women. They also are likely to be more dependent on nearby grocery stores and supermarkets because of limited transportation options and fewer economic resources.”
The findings showed significant geographic disparities regarding the availability of supermarkets. However, the majority of the women lived within 1 mile of a small grocery store. Dzewaltowski said this is important because previous studies have indicated that rural areas are food deserts where low-income residents have to travel far to access healthful foods.
The number and types of stores available differed in the metropolitan, micropolitan and rural areas. Rural low-income women had 74% fewer supermarkets and 55% fewer small grocery stores available within a 1-mile radius as compared to women in metropolitan areas. Yet the number of convenience stores per 10,000 residents was highest in rural areas.
Dzewaltowski said the findings indicate that the choice of supermarkets may be a more relevant issue than the availability of supermarkets. The findings also suggest that most of the low-income women reside within the urban cluster of the micropolitan areas and are likely to be exposed to multiple fast food restaurants and other high-caloric density eating opportunities, which are often absent in rural areas.