Well, it's hard to say...but it will definitely make me skinny. That's because I live in a walkable neighborhood and I value walking. It's that last part that is the key to low Body Mass Index (BMI), according to this recently published study from the International Journal of Behavioral Nutrition and Physical Activity. Living in a walkable community isn't enough. You also have to want to walk.
First, some background. It's clearly established that there is a relationship between walkable communities and walking. A pedestrian-friendly neighborhood has more pedestrians, plain and simple. What's less clear is why exactly this is so. Is there more walking in pedestrian-friendly neighborhoods because people who already like to walk a lot move into them? Or does walkable community design cause erstwhile couch potatoes to get up and move? A growing body of evidence suggests it's the former of these two possibilites that explain the high walking rates in pedestrian-friendly communities, and this study adds to that evidence.
The authors looked at three groups of people: those who valued walkability and moved to a new neighborhood during the course of the study, those who didn't value walkability and moved, and those who didn't move at all. They found that the folks who didn't value walkability and moved had larger increases in BMI than those who moved and rated walking as important, while the people who didn't move showed no change in BMI. As the authors write, this suggests that, "...walkable neighbourhoods attract walkers and if you are not interested in walking a walkable neighbourhood will not make a difference."
The study also found that walkability was "not a significant influence" on BMI, further suggesting that just living in a walkable neighborhood won't prevent obesity. Instead, if you want to get skinny you have to be like me and live in a walkable neighborhood because you want to walk.
Now, before we become entirely discouraged, the study does point out that neighborhood walkability may influence physical activity, even if it doesn't influence BMI. Perhaps people in walkable neighborhoods are moving more, just not enough to lead to weight loss. And this is important, because as I'll show in tomorrow's post, walking a few blocks can do your mind a lot of good, even if it doesn't do anything for your waistline.