Neighborhood fast food availability related to an individual's fast food consumption

The federal government has made one of its priorities reducing "food deserts," areas in which healthy food is difficult to find, according to background information in the article. "Such policies stem from limited evidence that food resources are related to obesity and are inequitably allocated according to neighborhood wealth," write the authors. "Implicit in these policy initiatives is that reduced access to fast food and increased access to supermarkets will translate into improvements in diet behavior and health."

Janne Boone-Heinonen, Ph.D., from the University of North Carolina at Chapel Hill, and colleagues assessed this assumption using data from the Coronary Artery Risk Development in Young Adults study, from its baseline in 1985 until 2001. The authors evaluated fast food consumption, diet quality and adherence to fruit-and-vegetable-consumption guidelines as a function of fast food chain, supermarket or grocery store availability within distances of less than one kilometer to more than eight kilometers from study participants' homes. The 5,115 participants (ages 18 to 30 years at baseline) in Birmingham, Ala.; Chicago; Minneapolis; and Oakland were asked how often they ate fast food, and detailed their food consumption during the prior month as well as usual dietary habits.

Among participants at lower income levels, an association between fast food consumption and fast food availability was observed. This relationship was particularly noticeable among men who had access to fast food between one and three kilometers from where they live. The findings did not suggest strong relationships between supermarkets and diet quality or consumption of fruits and vegetables. Availability of grocery stores had a mixed relationship with eating habits.

"These findings have critical implications for existing and proposed policies aimed at improving access to healthy foods," write the researchers. "Overall, classification of food stores and restaurants into 'healthy' or 'unhealthy' according to mode of service (fast food or sit-down) or size (supermarket vs. grocery store) may provide little understanding of how the food environment impacts diet and may overlook innovative policy solutions." The authors call for further research into the effect of the neighborhood food environment on diet and consumption.

Commentary: Food Deserts or Food Swamps?

An accompanying commentary by Jonathan E. Fielding, M.D., M.P.H., and Paul A. Simon, M.D., M.P.H., from the Los Angeles County Department of Public Health and the University of California, Los Angeles, provides perspective on the findings by Boone-Heinonen and colleagues. The association between fast food consumption and availability is relevant to an effort that Los Angeles has initiated to limit fast food restaurants in low-income neighborhoods, they write. Fielding and Simon also speculate whether inclusion of data about food quality, pricing and merchandising might provide more conclusive evidence about the relationship between supermarket availability and dietary behaviors.

"The greatest challenge in this area of research is how to address the complexity of local food environments," they state. "In many disadvantaged communities, the food environment is more swamp than desert, with a plethora of fast food; convenience stores selling calorie-dense packaged foods, super-sized sodas, and other sugar-loaded beverages; and other nonfood retail venues selling junk food as a side activity." Reducing access to these products, remark Fielding and Simon, may do more to reduce obesity than might increasing access to healthy foods. "Given the complexity of food environments," they conclude, "it will be important to identify those combinations of interventions that together generate meaningful improvements in dietary practices at the population level and reduce the huge disparities in overweight and obesity."