LANSING, Mich., March 4 (UPI) -- If U.S. adults have access to a vehicle they have access to produce, but if they have to walk to get food, finding lettuce may be impossible, researchers say.
Phil Howard and Kirk Goldsberry, both of Michigan State University, developed interactive maps using geographic information systems that offer a visual perspective of urban food deserts -- areas where food, especially fresh food, particularly produce, is hard to find.
Many supermarkets have closed stores that serve urban areas and moved to the suburbs, leaving mom-and-pop stores with little selection and little fresh food. Rural areas experience similar food deserts, often with only convenience stores or gas stations selling food.
"The change in food environments is recurring all over the nation," Howard said in a statement. "The best selection of produce and the lowest prices have moved to the suburbs. So if you want lettuce in Lansing, (Mich.) or in most U.S. cities, you're going to have to drive to get it."
The maps showed that less than 4 percent of the population in Lansing, Mich., lived within a 10-minute walk of a supermarket.
People with cars can overcome many geographical obstacles to obtain fresh produce while pedestrians' ability to obtain fresh produce is becoming increasingly challenging, Goldsberry said.