An interesting 2006 study titled "Food store availability and neighborhood characteristics in the United States" by Lisa M. Powell, Sandy Slater, Donka Mirtcheva, Yanjun Bao and Frank J. Chaloupka found that national trends mirror that of what I found in the Sixth Suffolk: that low-income neighborhoods have fewer chain supermarkets "with only 75% (p < 0.01) of that available in middle-income neighborhoods."
The study also had some interesting things to say about chain stores, larger groceries and small markets where people shop for food. When I started my study, I assumed that most people would want to shop like I do--in a convenient, large, chain grocery. Once I started the survey of groceries in the Sixth Suffolk though, I realized that people were shopping in smaller, sometimes specialized markets, and realized that perhaps I was putting my own assumptions onto populations that perhaps shopped differently than I.
Powell et al speak a bit to this assumption in the study which found that African-American populations prefer to shop in chain groceries, but that chains don't often locate in African-American neighborhoods and that this finding holds across economic scales. The study also found that Asian-Americans do prefer to shop in non-chain stores, likely to access specialty foods. Hispanic populations are apparently a bit split.
The lack of access to supermarkets also has a dietary impact according to the study:
Larger sized food stores such as supermarkets versus smaller stores and chain versus non-chain supermarkets have been shown to be more likely to stock healthful foods and to offer foods at a lower cost. Food costs are found to be associated with diet quality, and studies reveal significant correlations between diet quality and the availability of healthful foods in stores.
Potential barriers to obtaining a variety of healthful foods due to a lack of local area food stores such as supermarkets are likely to adversely affect dietary patterns and contribute to the risk of obesity. The availability of supermarkets has been associated with more fruit and vegetable intake, more healthful diets, and lower rates of obesity. Shopping at supermarkets versus independent grocers has been associated with more frequent fruit and vegetable consumption.
