From an article in this week’s issue of The Economist:
This part of Chicago’s South Side is in the heart of one of America’s many food deserts. These are notable not for the absence of food, but for the kind of food available. Though crisps, sweets and doughnuts are easy to come by, an apple is a rare commodity. Yet all the evidence shows that poor access to quality food results in a higher risk of obesity, diabetes and cancer — and more avoidable deaths.
Although cynics might argue that the market gives people the food they deserve, research published this month in the New England Journal of Medicine suggests otherwise. During the 1990s, when the American government paid for around 1,800 women to move out of public housing, the women who had moved showed a 20% lower rate of obesity and diabetes than those who had not. In other words, their improved environment (which many assume would include better shops) led to their better health.
This article by Marcel Fafchamps and Ruth Vargas Hill lists many scholarly references on food deserts. In particular, I would check out those by Alcaly and Klevorick (1971), Caraher et al. (1998), Goodman (1968), Whelan et al. (2002), and Wrigley et al. (2002).