By Susan Levine
Washington Post Staff Writer
Monday, November 5, 2007 3:58 PM

Blacks in the District aren't the heaviest in the country, and whites who are D.C. residents aren't the skinniest, but the difference in their rates of obesity is among the biggest of any city or county in the United States.

The District's fat gap put it in first place of the 164 jurisdictions examined by researchers at Vanderbilt University. The study, released today at the annual meeting of the American Public Health Association, used a national survey to focus on geographic variations in obesity in black and white populations.

Richmond also made the top ten because of the disparity in the obesity rates of its residents. In Maryland, Charles County came in 10th among jurisdictions with the least prevalence of obesity among African Americans, while Montgomery County earned distinction because rates for both its black and white residents were, relatively speaking, so low.

The study was not intended as a definitive or comprehensive look at a health issue that has reached epidemic proportions in the last 20 years in the United States. "It's more of a 'proof of concept' " showing the differences between rural and urban, north and south, said associate psychology professor David Schlundt, one of the authors.