‘Walkable’ Neighborhoods Mean Thinner Residents in Large Utah Study

Newswise — Commuters trekking into the office from the outer edges of suburbia should take note: It might be healthier to settle in an old neighborhood close to town and walk to work. According to a large new study, the more "walkable" an area is, the less residents are at risk for having excess weight.

"Older neighborhoods have been designed in ways that support healthy choices, although until recently researchers have not thought about this connection," said study co-author Barbara Brown. "Older neighborhoods often have bundles of design features, such as tree-shaded sidewalks, convenient small shops, bus stops, places to work and attractive destinations that give residents a reason to walk."

Brown is an environmental and social psychologist at the University of Utah. The study appears in the September issue of the American Journal of Preventive Medicine.

The researchers used census and driver license information along with body mass index data for more than 450,000 adults living in Salt Lake County, Utah. The body mass index (BMI) measures a person's weight in relationship to height. A "normal" range is 18.5 to 24.9; anything higher is "overweight" or "obese."

For men that live in older areas with high levels of population density and pedestrian-friendly street designs, walking to work is associated with a reduction in body mass. For example, a hypothetical 6-foot, 200-pound man living in a neighborhood without good sidewalks and interconnected streets would be 10 pounds heavier than his counterpart in a more walkable neighborhood would.

"For a woman of the sample's average height (approximately 5 feet, 5 inches) and weight (149 pounds; 24.9 BMI), the most-walkable neighborhood would be associated with nearly six fewer pounds (BMI 23.9) than the least-walkable neighborhood," the study showed.

The authors found an association between people with lower body mass and older neighborhoods — generally built before most residents owned cars. "Adding a decade to the average age of neighborhood housing decreases women's risk of obesity by 8 percent and men's by 13 percent," they wrote.

Ethan Berke, a physician and epidemiologist at Dartmouth Medical School, said researchers struggle to assess how community design affects exercise behavior. In this particular study, he said, "Their definition of neighborhood was suspect. They were only able to get age of housing in census tract [data]."

A census tract can cut across a broad area. Tracts have 2,500 to 8,000 residents and boundaries that follow visible features, according to U.S. Census information. These might not correspond to neighborhoods and natural environments that people interact in on a daily basis. Moreover, people interested in good health might choose to live where they know they can exercise easily, Berke said.

Still, he said that the new research is valuable. "I think there is hope to get people to walk more. Cities are experiencing resurgence," he said. "There is the possibility to do the right kinds of design."

American Journal of Preventive Medicine: Contact the editorial office at (858) 457-7292 or [email protected].

Smith KR, et al. Walkability and body mass index: density, design, and new diversity measures. Am J Prev Med 35(3), 2008.