In the American Journal of Epidemiology, a well-known set of authors that have published widely on the Framingham Study in the past have looked at BMI and proximity to fast food. I find it a bit of a reach to say that “contrary to much prior research, the authors did not find a consistent relation between access to fast-food restaurants and individual BMI” when, at first glance, there are clear confounders.
Regardless of how close the “negatives” of fast food outlets are, easy access to “positives” like parks, swimming pools, gyms and cheap fresh food markets is going to have a significant impact on peoples’ choices about what they do and eat. More simply, it doesn’t really matter how close that McDonalds is (see below) if you have access to safe parks, cycleways and a range of good quality cuisines.
adam g. dunn 