Scientists are starting to make the case that smart city planning—i.e. walkable, dense neighborhoods full of mixed land use—is the unexplored key to battling American obesity.

Researches recently found a significant link between where people live and their health—people who live in sprawling suburbs walk less, weigh more, and are generally unhealthier. People living in the suburbs are on average six pounds heavier and loads unhealthier than their city-dwelling counterparts. Via NPR:

So urban planners and health researchers are now saying all neighborhoods should be designed with density and walkability in mind—instead of cars and sprawl. Although, these professionals also admit that, "there's a lot of inertia in local government [to do so]," says Chris Nelson, from the Urban and Regional Planning Department at Virginia Tech.