Bob Stefko Inside the Fresh Moves mobile grocery store — housed in a donated city bus — in Chicago

Every morning, Madison, Wis., grocer Jeff Maurer fills a 40-foot air-conditioned trailer with fresh food from his local store, Fresh Madison Market, and drives to low-income neighborhoods to sell his wares. Maurer launched his nonprofit grocery-on-the-go, Freshmobile as he calls it, on July 2, in an effort to bring more fruits and veggies to communities with limited access to supermarkets and healthy food.

“I got involved with the Boys & Girls Club and it was clear the kids weren’t getting fresh fruit,” says Maurer. “I would bring it in, and they’d devour it, but they couldn’t buy it in their own neighborhood. Every kid should have access to blueberries and strawberries.”

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Initiatives like Freshmobile, designed to help improve the diet of people living in neighborhoods where quality fresh foods are hard to obtain, have been quite literally “popping up” all over the country. This summer, several temporary and mobile pop-up markets will set up shop in so-called food deserts — low-income areas that are more than a mile away from the nearest grocery store — to sell mangoes, melons, lettuces, onions and other fresh fruits and vegetables.

The movement first got going in 2003, when a Bay Area group introduced organic food to West Oakland neighborhoods in a roaming solar-powered, biodiesel-burning food truck. Over the years, the mobile market idea gained steam. In June 2011, Fresh Moves, a Chicago non-profit launched its one-aisle grocery store on board a donated Chicago Transit Authority bus, and currently serves Chicago’s West Side neighborhoods. This August, the Seattle-based group Stockbox Grocers will launch its first store in the city’s South Park neighborhood, serving healthy food and to-go meals out of reclaimed shipping containers and storefronts. Residents of Portland, Ore., Kansas City and Baton Rouge are also seeing groceries-on-the-go rolling through this summer.

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In 2009, the USDA mapped out the nation’s food deserts, tracts that are home to some 23 million Americans. About 10% of the 65,000 census tracts in the U.S. are considered food deserts. Data show that people living in these neighborhoods have limited access to a healthy diet, which can therefore lead to higher levels of obesity and other weight-related illnesses, such as diabetes and heart disease. So, can pop-up markets solve the food desert problem? Maybe.

Researchers have found that while people are more likely to buy and eat healthy, fresh food if it’s available, improving community health requires much more than simply installing a grocery store. In 2011, a 15-year study found that upping the number of grocery stores in a community didn’t change customers’ buying behavior. People may shop at new supermarkets, but that doesn’t mean they automatically buy healthier food.

“Just because you build it, doesn’t mean you will change people’s behavior,” says study author Barry Popkin, a professor of public health at the University of North Carolina at Chapel Hill. “Price, quality, accessibility, incentives, they matter too. Every community is different, but new efforts or supplementing existing infrastructure works if they’re accompanied with affordable prices, education, promotion or community collaboration.”

That is, introducing more places to buy food doesn’t translate into better choices unless people are educated about what those better choices actually are.

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For example, the Fresh Moves staff found that if they provide relevant health tips — like the fact that organic fruits are free of potentially harmful pesticides — their customers will buy more organic strawberries, even if they’re more expensive. “Sometimes people are just unaware of the options, but they’ll buy it if they know about it,” says Fresh Moves board president Steve Casey.

Bob Stefko

There’s also research showing that the shopping environment itself helps determine whether people buy healthy stuff. A recent study published in the journal Public Health and Nutrition found that people are more likely to buy fruits and vegetables not only if they’re cheap and easily accessible, but also if shoppers are satisfied with their choices and the quality of the merchandise.

The study looked at data from 495 people in low-income Chicago communities. The participants reported their fruit and vegetable consumption as well as their shopping habits and shopping environments. “We found in our study that people who perceived they were getting better selection, quality and convenience ate more fruits and vegetables,” says study author Jonathan Blitstein, a research psychologist at Research Triangle Institute in North Carolina. “Low-income people have the same expectations as higher-income people. When they shop for fruits and vegetables, they look for a lot of the same things.”

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These data suggest that efforts to encourage owners of corner stores and markets — which are commonly found in food deserts and typically sell only packaged, high-sugar, high-fat foods — to provide healthier options will benefits customers only if the bananas and apples near the register aren’t old and bruised, and if the store itself offers an atmosphere that will draw shoppers in.

Stockbox Grocers founder Carrie Ferrence says, “South Park has convenience stores that have a lot of grocery staples, but they don’t offer an experience that’s really inviting or welcoming.” In conversations with community members, Ferrence found that people talked less about the food they were missing and more about how they felt in the store. “They say, ‘There’re people drinking outside and I won’t bring my kids there,’ or ‘I don’t want to walk past four aisles of junk food to get to the one aisle of groceries,’” says Ferrence. “People are really reaching out for a grocery experience that more affluent communities have access to.”

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There’s a big difference between accessibility and availability, in other words. “Produce may be available to people, but it’s not accessible if you don’t view the offerings as worth your time and money,” says Blitstein.

Blitstein has some advice for community planners or would-be pop-up grocers hoping to establish new projects to bring healthier dietary options to U.S. communities that need them: get to know your community first. What works in one region of the country or for one particular ethnic group may not necessarily work for another. “One of the most important things someone can do when designing their project is talk to the people,” says Blitstein. “Food is very culturally based and what is viewed as acceptable is often a function of what the culture expects. It’s important to let the people have a voice if you plan on changing their community.”