Kids in Suburban Sprawl More Likely to be Obese

A study in the December issue of the American Journal of Preventive Medicine reports that, like their parents, kids who live in the suburbs and usually ride in cars, weigh more and are more prone to obesity than kids who live in densely populated urban areas where they can easily walk to destinations.

Said study leader Reid Ewing, of the University of Maryland 's National Center for Smart Growth, "After accounting for economic and demographic differences, adolescents surveyed in 1997 were more than twice as likely to be overweight if they lived in a sprawling county compared to a compact one.

"The most likely reason--those living in sprawl are effectively living in their cars. They are getting little exercise walking as part of their daily lives, have less time to be physically active, and may even consume more calories as cars become de facto snack shops."

Ewing led the 2003 study that first reported a relationship between sprawling adult waistlines and sprawling metropolitan areas. That study estimated that the average adult living in dense and walkable Manhattan would weigh about six pounds less than an adult of the same age, race, and other personal characteristics living in the most sprawling suburban county, Geauga County outside Cleveland . By late 2005, this study was the most widely cited in the Social Sciences.

Ewing 's co-authors in this latest study are David Berrigan of the National Cancer Institute and Ross Brownson of Saint Louis School of Public Health.

First Look at Kids

"This novel finding, that where you live can affect your weight, has been challenged, tested, and generally validated since then, but never for kids," said Ewing . "Kids have become the focus of concern at the Centers for Disease Control and Prevention and other health agencies, since obese kids tend to become obese adults, with life-long health problems and associated elevated health care costs."

Ewing looked at a sample of 9,000 young Americans, first surveyed in 1997 for the Department of Labor's National Longitudinal Survey of Youth. Five years later, when the same youth were surveyed as young adults, the likelihood of being obese was, again, more than twice as great for those living in sprawling communities.

"There was a wrinkle to these results, however, which initially stumped us," said Ewing . "A significant association between urban sprawl and weight didn't emerge for youth moving from one place to another. One possibility was that environmental effects take time to show up in weight gain. Good or bad habits with respect to physical activity and eating may die hard after a move.

"But a re-look at the data provided an additional insight. The effect of sprawl is one-way. Those moving from sprawl to dense areas tended to lose significant amounts of weight, while those moving in the opposite direction were largely unaffected. The move from the most sprawling metropolitan county to the most compact would be expected, in the short-term, to take a pound off the average American youth. In the long term, the effect would be much greater."

Glued to the Tube

The amount of TV watching proved to be an even stronger independent predictor of overweight in these adolescents, Ewing said. "Regardless of where they lived, frequent TV watchers tended to be heavier, and frequent exercisers lighter."

For parents in sprawling America , Ewing said that short of moving to walkable places, "Find a way to compensate for car-dependent sprawl. Get kids into sports and away from television."

Funding for this study of youth obesity came from the National Cancer Institute, National Institutes of Health.

See the online article in the American Journal of Preventive Medicine

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