New York City’s obesity rate has climbed in recent years, but there are large variations across the city’s neighborhoods, with lower income areas hit hardest, a new study finds.

Between 2003 and 2007, the prevalence of obesity citywide increased from 20 percent to 22 percent, according to the study, published in the American Journal of Epidemiology.

That was still lower than national and statewide rates, which stood at roughly 27 percent and 25 percent around the same time period. And some city neighborhoods remained steadfastly slim.

In more affluent areas like the Upper East Side, Chelsea and the West Village, obesity rates hovered around 8 percent across the study period.

In contrast, obesity was a more common and growing problem in other city neighborhoods, many of which are lower-income. In 2003, only one neighborhood - East Harlem - had an obesity rate higher than 30 percent. By 2007, six neighborhoods had joined it: three in the Bronx, the Bedford-Stuyvesant neighborhood of Brooklyn, Rockaway in Queens and northern Staten Island.

It’s no secret that the collective U.S. waistline has been expanding in recent decades. But the problem does not affect all areas of the country - or even all areas of a single city - equally.

Understanding neighborhood-by-neighborhood variations could help in efforts to combat obesity, according to Dr. Jennifer L. Black of the University of British Columbia in Vancouver, Canada, the lead researcher on the new study.

“If we can figure out what types of neighborhood characteristics make it easier for people to make healthy choices, and what kinds of factors are barriers to good health,” Black told Reuters Health by email, “we will be able to come up with more effective interventions to help people maintain a healthy body weight and reduce their risks of chronic diseases like type 2 diabetes and heart disease.”

Black and colleague James Macinko, of New York University, found that certain neighborhood features - a wider variety of food stores and more fitness centers - were associated with lower obesity rates.

The finding does not prove that better food selections and gyms prevent obesity. “But what this study does tell us,” Black said, “is that substantial differences (in obesity) exist between neighborhoods with different levels of access to food and fitness amenities.”

And such neighborhood features, she added, remained linked to obesity even when the researchers accounted for factors like residents’ age, race and education levels - which were gathered from an annual health survey that covered more than 48,000 New Yorkers in 34 city neighborhoods.

The findings, according to Black, suggest that “it’s worth taking these kinds of (neighborhood) factors into account when looking for solutions to rising rates of obesity.”

The researchers note that New York City recently launched a “Green Cart” program designed to offer lower income residents a better selection of fresh produce. The city made available 1,000 new permits for mobile carts selling raw fruits and vegetables to be set up in specified “underserved” neighborhoods in the city’s five boroughs.

SOURCE: American Journal of Epidemiology, online February 19, 2010.