Living far away from food may make you fatter.
That was the surprising finding of a group of University of Utah researchers, who looked at the body mass index of 500,000 Salt Lake County residents and compared those who live within a half-mile of retail food outlets to those who don't.
People who have closer food options -- whether supermarkets, restaurants or fast food -- were 10 percent less likely to be obese, they discovered.
Getting out and walking, even if it's to grab a hamburger, burns more calories than driving to get one.
"In some sense, what we're getting is this a neighborhood where there are a lot more reasons to walk," said Cathleen Zick, co-author of the 2008 study and a U. professor of family and consumer studies.
Slated to be published in the November issue of Social Science and Medicine , the study revealed that roughly 30 percent of Salt Lake County neighborhoods are "food deserts," with no retail food outlets.
A larger percentage of residents living in higher-income areas did not have close access to such businesses -- not that surprising, considering many better-off families live in suburbs, Zick said.
But while fewer low-income residents can't walk to places where they can buy food, the impact on them is more pronounced. When comparing residents in one low-income neighborhood to the next, the researchers found that those who can walk to a supermarket are 14 percent less likely to be obese.
"If they don't have private transportation, then they're very limited in their access," Zick said.
Interestingly, higher-income residents' waistlines benefited more from living near a restaurant than a grocery store. Zick speculates that's because they would drive to a grocery store anyway, while dining out may encourage walking.
The study underscores the benefits of the "new urbanist" designs -- Daybreak in South Jordan is one example -- that blend residential and retail development, Zick said.
In Salt Lake City, the 9th and 9th, and 15th and 15th areas, while not new, are magnets for neighborhood walkers. As developers look forward, she said, "we should be thinking in terms of those types of designs."
New University of Utah research concludes that having more food options helps fight obesity. It combined three types of data:
Who's walking? » Researchers assessed the walkability of 566 census-block groups in Salt Lake County, looking at population density in 2000 and how many residents walked to work.
How far to food? » Using the 2008 Dun and Bradstreet directory, they located food-related business within those blocks.
Who's healthy? »They calculated the body mass indexes of 453,927 Salt Lake County residents, ages 25 to 64, from the blocks. They used height and weight data from the U.'s Utah Population Data Base.
Want to check your BMI?
Body mass index is calculated using height and weight to screen for obesity. Find a calculator at www.nhlbisupport.com/bmi/.