Two recent stories (via Planetizen: here and here) make the connection between health and how we design our urban environments and transportation systems:

• Five New York City departments have jointly released a document titled “Active Design Guidelines: A new definition for sustainable cities“, covering everything from Urban Design to where to put the stairwells in buildings (hint: make it easier to find the stairs than the elevator).
• A study out of Berkeley has found that kids living in calmer traffic areas are less obese than those living near heavy traffic.