People who live in neighborhoods with safe sidewalks, ample parks, good public transportation and ready access to fresh fruits and vegetables are 38 percent less likely to develop diabetes than others, U.S. researchers said on Monday.

They said unlike a lot of other factors that influence diabetes, creating a healthy neighborhood is one thing policymakers can do to address the epidemic of diabetes, which costs the United States more than $116 billion in medical expenses each year.

An estimated 23.6 million people in the United States and 246 million people globally have diabetes. Most have type 2, the kind linked with a poor diet and lack of exercise.

Altering our environments so that healthier behaviors and lifestyles can be easily chosen may be one of the key steps in arresting and reversing these epidemics, Amy Auchincloss of Drexel University in Philadelphia, whose study appears in the Archives of Internal Medicine, said in a statement.

Auchincloss studied 2,285 adults age 45 to 84 from three different communities: Baltimore, Maryland; the Bronx neighborhood of New York and Forsyth County, North Carolina, who were initially examined between 2000 and 2002. They took blood sugar levels before the study and at three follow-up exams, and gathered information on physical activity, weight and diet.

They also measured neighborhood resources through a community survey that asked about whether it was easy to get healthy foods, or if it was pleasant or easy to walk in their neighborhood.

They defined neighborhoods as the area within a 20-minute walk or a mile from their homes.

In communities that offered more healthy resources -- ranked by a combined score for opportunities for physical activity and healthy foods, people were 38 percent less likely to develop type 2 diabetes in five years than people who lived in less-healthy neighborhoods.

Several studies have found that lack of access to healthy foods in poor neighborhoods contributes to obesity. And a study last year published in the American Journal of Public Health, found that youth whose schools are located near a fast food outlet eat fewer fruits and vegetables, drink more soda and are more likely to be obese than students at other schools.

Although it is difficult to force an individual to make changes that alter their diabetes risk, it may be possible to lower the incidence of diabetes in a community by making neighborhood improvements, Dr. Mitchell Katz of the San Francisco Department of Public Health, said in a commentary.

If we are to decrease the rates of type 2 diabetes, we need to change the environment in ways that make it easy for people to exercise and eat right as part of their daily routine, Katz wrote.

Medicine