Experts have a term for neighborhoods with little or no access to nutritional foods: food deserts. But that doesn't mean there isn't plenty of food around-it's just the wrong kind.

In general, food deserts contain a glut of fast-food joints, chain restaurants, and convenience stores, and few supermarkets or grocery stores that offer fresh produce.

Living in a food desert for too long may compromise your health. Studies have shown that people who don't have easy access to a supermarket tend to have a less healthy diet and are more likely to be overweight, even if their neighborhood features a variety of restaurants, including healthy ones.

"Walking to a restaurant in your neighborhood is not the same thing as walking to the supermarket to buy groceries," says Andrew Rundle, an associate professor of epidemiology at Columbia University's Mailman School of Public Health, in New York City, who has researched the link between supermarket proximity and body mass index (BMI), a ratio of height to weight.

A lack of supermarkets is often a problem in the inner city, where space and rents come at a premium. But not everyone suffering from a shortage of healthy food options lives in the city. Although they receive less attention, food deserts can pop up in the countryside, too.

Rural areas are often too sparsely populated to sustain local supermarkets, and the small markets and grocery stores once found in small towns across the U.S. are increasingly being replaced by larger, regional stores, says Lois Wright Morton, PhD, a sociologist at Iowa State University, in Ames.

"Here in Iowa, market forces have consolidated smaller grocery stores into superstores with more square footage, more products, and therefore drawing from a larger geographic area," she says. "If you don't have access to a car, and aren't on a train or bus line, then how do you get there?"



You can't walk your way out of a food desert
It would make sense that living in big cities, sidewalk-lined suburbs, and other areas that encourage walking would be good for your waistline. If you commute or run errands on foot, you'll burn more calories than you will sitting behind the wheel of a car.

But it turns out that the exact opposite is often true. Many walkable urban neighborhoods have high obesity rates, and not only because people who live in the inner city tend to be less affluent (and less healthy).

Research suggests that even if a neighborhood is walkable, it's not enough to counteract the food-desert effect. If the pedestrian-friendly sidewalks surrounding your house lead to fast-food restaurants and convenience stores rather than supermarkets stocked with fresh fruits and vegetables, the extra fat and calories you'll consume in the long run may outweigh the health benefits of all that walking.

Ideally, your neighborhood will help you strike a balance between the energy you take in from food and the energy you burn off through walking and other exercise. If that balance is out of whack, you may find your waistline growing. Where people live "affects both [their] ability to expend energy through exercise and also consume energy through eating," says Samina Raja, PhD, an associate professor of urban and regional planning at the University of Buffalo.

In a study published in April, Raja and her colleagues examined the connection between the physical layout of various neighborhoods in and around Buffalo and the BMI of nearly 200 women living there. Surprisingly, the "walkability" of the neighborhoods-which ranged from the inner city to semirural exurbs-did not appear to influence BMI.

But the type of food stores did. Women who lived near a large number of restaurants, or in closer proximity to a convenience store relative to a grocery store, tended to have a higher BMI. Each additional restaurant within a five-minute walk was associated with almost a one-point increase in BMI, for instance. (A person with a BMI of 30 or higher is considered obese.)

This connection wasn't only due to the fact that neighborhoods with lots of convenience stores are often more downscale. (In the U.S., obesity rates tend to rise as income falls.) The researchers took the women's socioeconomic status into account, and they found that the food options in a woman's neighborhood influenced her BMI nearly as much as her financial situation.

"We should really be aiming to make it easier for people to access fresh fruits and vegetables," Raja says.



Finding a food oasis
If you find yourself living in a food desert, don't resign yourself to a diet of fast food and frozen dinners. Although it may take some digging to find them, the sources of fresh food are growing.

Community-supported farms are an often-overlooked resource, Raja says. These farms provide shares of fresh fruits and vegetables to families that buy into the farm at the beginning of a growing season, and often deliver to neighborhoods that are underserved by grocery stores and supermarkets.

Residents should ask around or visit the website LocalHarvest to see if there is a community-supported agriculture (CSA) drop-off in their neighborhood, Raja says. "This also provides people a chance to participate in improving their local food system," she adds.

Efforts to bring back local grocery stores are also under way across the country. In some places, towns have bought land, put up a store, and leased it to a private company to run, enabling residents to once again walk to the store. "Of course, the community needs to be committed to shopping there, rather than at a larger store on their way home from work in the big city," says Morton. "Otherwise, it will go out of business."

Rundle's research, meanwhile, has been part of the basis for a new city-led initiative in New York City that aims to create oases in the city's food deserts by offering tax breaks to grocery stores that promise to set aside a certain amount of shelf space for fresh fruits and vegetables. The city has also invested in a fleet of fruit and vegetable carts to help fill in some of the grocery store gaps, as well as offering incentives to small convenience stores to carry more produce.

"The city is providing people with new healthy choices in hopes that people will respond to that availability," Rundle says.

And if you're moving to a new neighborhood and want to avoid getting stranded in a food desert, Raja suggests asking your realtor for areas that have grocery stores within a safe walking distance. Or you can see for yourself how walkable a potential neighborhood is at Walkscore.
Last updated: Aug 30, 2010