This article from Smart Growth Online looks at the increasing concentration of fast food restaurants in many cities and the resulting impact on public health, and also offers some advice to communities for using land use strategies to limit the i
"In communities where grocery stores have become scarce, it is common to see fast-food restaurants filling the food retail void. For households with inadequate access to transportation and limited budgets, fast food can be a primary food source in these neighborhoods. A recent study in Chicago linked an 'imbalanced food environment' (where the number and location of fast-food outlets was greater than the number and location of grocery stores) with increased body mass index (a measurement that can indicate obesity and overweight)."
"The cumulative impact of these environmental components-scarce grocery stores, plentiful fast food, and limited access to physical activity-is manifested in the obesity epidemic."
The article also argues that land use regulations can be altered to allow more healthy alternatives to fas food restaurants, such as community gardens and farmers markets.