Obesity's Home: City or Suburbs?

Feb. 23, 2006 -- Urban sprawl may not deserve blame for obesity, researchers report.

Siim Soot, PhD, and colleagues analyzed the height, weight, and home addresses on the drivers' licenses of about 7 million Chicago-area residents. The researchers calculated each person's BMI (body mass index, which is based from one's height and weight). Body mass index is used as an estimate of body fat.

Suburbs close to Chicago had residents with the lowest BMIs. The most distant suburban areas were similar, in terms of BMI, to most city neighborhoods.

When it comes to obesity, a person's income and education probably trumps location, the researchers note.

Soot's team works at the Urban Transportation Center of the University of Illinois at Chicago (UIC). They presented their findings to the Transportation Research Board of the National Research Council, states a UIC news release.

Sleek Suburbs?

If Soot's study is right, it dents the theory that city dwellers are leaner because they walk everywhere, while suburbanites bulk up behind the driving wheel.

"There is scant evidence that obesity is directly associated with urban sprawl," write Soot and colleagues. Not all studies come to their conclusion, but those studies often didn't compare specific neighborhoods, Soot's team notes.

In their study, people with high incomes, college educations, and high home values tended to be leaner -- and many of those people lived in suburbs near Chicago. The opposite was also true, the study shows.

Fudge Factor

Many people fudge in reporting their weight for their driver's license. That little lie doesn't bother the researchers too much because they figure that just about everyone does it, regardless of where they live.

"It is very likely that the majority of individuals weigh more than the reported figure on their driver's license," the researchers write. "If everyone or most individuals weigh a fixed percentage more, then we do not have a problem" with the data.