Suburbs may make you fatter

New research suggests that it might for those who reside in neighborhoods designed more for cars than foot traffic.

People in the study who lived in the most walkable neighborhoods weighed an average of 8 pounds less than people who lived in the least walkable areas.

Neighborhoods built before 1950 tended to have sidewalks and other characteristics that made them more accessible to pedestrians, including being more densely populated and having restaurants and other businesses nearby, lead researcher Ken R. Smith, PhD, tells WebMD.

In general, newer neighborhoods offered fewer opportunities for walking.

The study appears in the September issue of the American Journal of Preventive Medicine.

“We aren’t saying the move from older to newer neighborhoods is the cause of the obesity epidemic, but it may be a factor,” Smith says.

Walk Less, Weigh More

In an effort to test the theory, Smith and colleagues calculated the body mass index (BMI) of 453,927 residents of Salt Lake County, Utah, using height and weight data from their driver’s license applications. Adults between the ages of 25 and 64 were included in the analysis.

The researchers also reviewed census data that included information about the neighborhoods where the residents lived.

In general, the research suggested that the more walkable a neighborhood was, the less likely its residents were to become overweight or obese.

Based upon the analysis, a man of average height and weight who lived in the most walkable neighborhood in Salt Lake County would be expected to weigh an average of 10 pounds less than a man living in the least walkable neighborhood. For women, the difference would be 6 pounds.

Smith says the growing emphasis on designing pedestrian-friendly places for people to live, work, and play could have a large, positive impact on health in the future.

He cites a recent report from the Brookings Institution predicting that by the year 2030 half the buildings in the United States will have been built since 2000.

“That represents a huge opportunity to think about how we are building our communities and to make them better places, both from a health and an environmental standpoint,” he says.

Walkability a Goal

This is the goal of the CDC’s ‘Healthy Places’ initiative, says Andrew Dannenberg, MD, MPH, of the CDC’s National Center for Environmental Health.

“Our mission is to get health on the table when building decisions are being made,” he says. “This has not been done much in the past, but awareness is growing.”

The recent stratospheric rise in gas prices and concerns about climate change have helped focus attention on the subject, but it is still too soon to know if the attention will lead to change, Dannenberg says.

The CDC’s ‘Healthy Places’ web site makes it clear that the challenge is daunting, as it calls for substantive changes with regard to future growth.

“Today, typical suburban homes sit in cul-de-sac subdivisions that empty out onto high volume roads,” it reads. “Zoning laws encourage the separation of residential areas from schools and shopping malls by long and often dangerous travel distances. Elementary school bicycle racks stand empty as parents fear for their children’s safety on narrow or traffic-laden roads. (And) pedestrians take risks as they cross dangerous intersections in communities where safe crosswalks are all but nonexistent,” the CDC statement reads.