With initiatives including the "Campaign to End Obesity" and Michelle Obama’s "Let’s Move!" campaign, the United States has started to make a unified effort to slim down. However, recent data shows it may not be enough. The Gallup-Healthways Well-Being Index, a poll gauging the nation’s fattest and thinnest cities, has revealed that obesity rates in America’s largest cities continue to reach over 15 percent.

"Rising obesity rates have significant health consequences for both individuals and communities of all sizes. Numerous social, environmental, economic, and individual factors may all contribute to physical inactivity and consumption of less healthy foods, two lifestyle behaviors linked to obesity," Healthways Lifestyle Solutions Director Janna Lacatell said in a statement. "In order to combat the trend and encourage individuals to make healthier choices, community-based policy and environmental approaches can, and should, be used."

Researchers from Gallup and Healthways used self-reported height and weight from at least 300 adults in 189 Metropolitan Statistical Areas (MSA) to calculate the average American’s Body Mass Index (BMI). According to the Centers for Disease Control and Prevention, a BMI between 18.5 and 24.9 is considered normal while a BMI over 30 is considered obese. People with BMIs over 30 run the risk of developing heart disease, type 2 diabetes, hypertension, and certain types of cancer.

Boulder, Colo., recorded an obesity rate of 12.4 percent, making it the country’s thinnest city for yet another year. Boulder has ranked in as America’s least obese city four out of the five years Gallup and Healthways has been measuring the country’s health. Colorado cities Fort Collins-Loveland and Denver-Aurora also scored high among the nation’s least obese with respectable rates of 18.2 percent and 19.3 percent. The entire state of Colorado comprised the second-lowest obesity rate in the U.S.

On the other end of the spectrum, cities in Texas and West Virginia didn’t fare so well under the country’s health standards. Considered the highest obesity rate in all 189 U.S. metropolitan areas, 39.5 percent of residents in Huntington-Ashland, W.Va.-Ky.-Ohio were most likely to record a BMI over 30. Resembling the statistics evaluated in the Huntington-Ashland community, two out of the five residents in McAllen-Edinburg-Mission, Texas, were considered obese between 2012 and 2013.

Overall, the country’s obesity rate of 27.1 percent is the highest Gallup and Healthlands has recorded since the poll’s advent in 2008. The research team attributed rising obesity rates in certain cities to a decline in healthy eating habits and lower work productivity. They also urged the reinforcement of government and local weight loss programs in smaller communities, seeing as they were more likely to record a higher obesity rate.

Least Obese Cities

1. Boulder, Colo. – 12.4%

2. Naples-Marco Island, Fla. – 16.5%

3. Fort-Collins-Loveland, Colo. – 18.2%

4. Charlottesville, Va. – 18.7%

5. Bellingham, Wash. – 18.7%

6. San Diego-Carlsbad-San Marcos, Calif. – 19.3%

7. Denver-Aurora, Colo. – 19.3%

8. San Jose-Sunnyvale-Santa Clara, Calif. – 19.5%

9. Bridgeport-Stamford-Norwalk, Conn. – 19.6%

10. Barnstable Town, Mass. – 19.6%

Most Obese Cities

1. Huntington-Ashland, W.Va.-Ky.-Ohio – 39.5%

2. McAllen-Edinburg-Mission, Texas – 38.3%

3. Hagerstown-Martinsbrug, Md.-W.Va. – 36.7%

4. Yakima, Wash. – 35.7%

5. Little Rock-N. Little Rock-Conwat, Ark. – 35.1%

6. Charleston, W.Va. – 34.6%

7. Toledo, Ohio. – 34.2%

8. Clarksville, Tenn.-Ky. – 33.8%

9. Jackson, Miss. 33.8%

10. Green Bay, Wis. 33.0%