Perhaps people exercise more in Colorado, but whatever the reason, the state has the fewest obese people in the country.

If you were to walk the streets of, say, Denver, you'd probably see more thin people than overweight ones. Colorado continues to have the country's lowest obesity rate, according to the latest Gallup poll results.

Twenty percent of Colorado residents are obese, compared to 34 percent of the people in West Virginia, which has the highest obesity rate in the United States. Colorado and West Virginia had the same top and bottom spots, respectively, in the 2010 survey.

The results are based on interviews of 177,237 Americans, ages 18 and older, conducted in January through June. Participants reported their height and weight, from which the researchers calculated body mass index. For this survey, BMI scores of 30 or higher were considered obese.

The nation's obesity rate has held steady from last year at 26 percent. It is slightly higher than the 2008 rate (25.5 percent). Even so, many of the country's most-obese states continue to see a trend in the wrong direction. For instance, last year about 27.6 of Delaware residents were obese; this year it's 33.6 percent. [US Loses Its Fat Supremacy]

Ten states with lowest obesity rates

Colorado: 20.1 percent

Utah: 21.6 percent

Connecticut: 21.7 percent

California: 22.1 percent

Rhode Island: 22.1 percent

Massachusetts: 22.6 percent

New Jersey: 22.6 percent

Nevada: 23.6 percent

Minnesota: 23.8 percent

Florida: 24.2 percent

Ten states with highest obesity rates

West Virginia: 34.3 percent

Delaware: 33.6 percent

Mississippi: 32.1 percent

Louisiana: 31.2 percent

South Carolina: 30.6 percent

Indiana: 30.5 percent

North Dakota: 30.2 percent

Oklahoma: 30.2 percent

Kentucky: 29.9 percent

Ohio: 29.0 percent

See list of all 50 states.

While some states improved from last year none had an obesity rate lower than 20 percent, suggesting "residents throughout the entire country have much work to do to begin to tackle the nation's obesity problem," according to a Gallup statement.

The obesity survey results, part of the Gallup-Healthways Well-Being Index, were weighted by gender, age, race, ethnicity in the case of Hispanic respondents, education, region, adults in the household, and phone status; in that way, Gallup said, the results should be nationally representative.

The full 2011 results should be available in early 2012, according to Gallup.

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