Does suburban living contribute to obesity?

Big-box stores are effective delivery devices for fattening foods, economists argue in a new study.

More from NPR reporter Alan Greenblatt:

The study, coauthored by researchers at the universities of Iowa, Virginia and Louisville, looks at the nation as a whole, rather than focusing in on specific locales (although Courtemanche says there are clear regional differences). The authors compared information they had compiled about restaurant and big-box-store locations with survey data looking at individual health, as well as state-level data examining more than two dozen economic and demographic factors.

What they found was that the density of restaurants and large-scale food retailers in particular areas was a major factor between 1990 and 2010 in the nationwide rise of obesity and BMI, or body mass index, which measures weight against an individual's height. They attribute nearly half the rise in severe obesity — referring to people who are more than 50 percent above their ideal weight — to such businesses.

Courtemanche concedes that it would be impossible to prove to a certainty that big-box stores and restaurants cause increases in obesity, "unless you're able to randomize which counties get a Wal-Mart and which ones don't." But he says even after controlling for other factors, such businesses have a measurable effect.

Today's Question: Does suburban living contribute to obesity?

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