Significantly lower blood pressure and lower rates of diabetes were also found in denser cities. The leading explanation is that people who live in more urban areas walk more, but the study's primary researcher says there's more to it than that.
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"The amount of time one spends in a car in a sprawling region is such that it eliminates time for a whole range of other activities, including those that are more active," said Reid Ewing, professor of city and metropolitan planning at the University of Utah. He said the development in those areas plays a role, too, "In sprawling areas strip-commercial development and fast food restaurants bias the food choices."
The study pegged the Hickory/Lenoir/ Morganton, N.C., metro area as the worst for sprawl. Atlanta, Clarksville, Tenn., Prescott, Ariz., and Nashville/Davidson, Tenn. rounded out the five worst areas for sprawl.
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Researchers looked at several factors to determine a city's ranking, including development density and population living near jobs. they also measured the walkability of the streets.