Ant writes "A Science News article talks about the relationship between city design and health. New cross-disciplinary research is exploring whether urban sprawl makes us soft, or whether people who don't like to exercise move to the sprawling suburbs, or some combination of both." From the article: "So far, the dozen strong studies that have probed the relationships among the urban environment, people's activity, and obesity have all agreed, says Ewing. 'Sprawling places have heavier people... There is evidence of an association between the built environment and obesity.' ... However, University of Toronto economist Matthew Turner charges that 'a lot of people out there don't like urban sprawl, and those people are trying to hijack the obesity epidemic to further the smart-growth agenda [and] change how cities look.' ... 'We're the only ones that have tried to distinguish between causation and sorting... and we find that it's sorting,' [says Turner]. 'The available facts do not support the conclusion that sprawling neighborhoods cause weight gain.'"