By Michelle Fox
CNBC.com

More than one-third of American adults are obese, according to the Centers for Disease Control and Prevention. The obesity epidemic has been going on for decades, and today health-care costs associated with obesity are estimated at $147 billion a year.

To be considered obese, a person has a body mass index (BMI) of 30 or higher. With the extra weight comes myriad health issues — obesity contributes to heart disease, diabetes, stroke, and some cancers.

Recently, the Gallup-Healthways Well-Being Index ranked the 10 most obese metropolitan areas in the U.S., offering perspective on the cities that are affected by the country’s obesity woes.

The health implications are apparent — of the metro areas with the highest obesity levels, 58 percent of their residents were more likely to report having had a heart attack over the course of their lifetimes, and 34 percent were more likely to report having high blood pressure.  Combined, residents of these cities also pay an estimated $1 billion more in medical costs each year thanks to their high obesity rates.

In 2010, the government announced its goal to lower the prevalence of obesity to 15 percent. In 2011, only three out of the 190 areas surveyed in the Gallup-Healthways Well-Being Index had an obesity rate below that level: Fort-Collins-Loveland, Colo.; Bridgeport-Stamford-Norwalk, Conn.; and Boulder, Colo. Boulder ranked as the least obese city, with an obesity rate of 12.1 percent.

It’s not all bad news, however. According to the CDC, although there was a rise in obesity between 1983 and 2000, the rates actually have stabilized over the past 10 years.

“There has been no change in obesity prevalence in recent years,” CDC scientist Heidi Blanck said. “However, over the last decade there has been a significant increase in obesity prevalence among men and boys, but not among women and girls overall.”

The government is aiming to eventually reduce the rate of obesity. In 2010, the Childhood Obesity Task Force released 70 recommendations to prevent and control childhood obesity.

Look ahead to see the most obese metro areas in the U.S., and how much their citizens are paying in obesity-related health-care costs every year, according to the recent Gallup survey.

10. Reading, Pennsylvania

Obesity rate: 32.7 percent

Annual obesity-related costs: $190.2 million

Located approximately 60 miles northwest of Philadelphia, Reading, Pa., ranks 10th on the Gallup-Healthways Well-Being Index. It’s the most obese city in Pennsylvania, which has a statewide obesity rate of 28.6 percent, according to the CDC .

With 88,000 people residing in the city, more than 28,000 residents are considered obese. In Reading, 10 percent report having diabetes, a chronic disease associated with obesity. Even higher than the obesity rate is the poverty rate: 35 percent of the population in the city lives below the poverty level. According to the nonprofit Food Research and Action Center, women and children in poverty are at the highest risk for obesity.

9. Kennewick-Pasco-Richland, Washington

Obesity rate: 33.2 percent

Annual obesity-related costs: $116.5 million

This metropolitan area in southeastern Washington is called Tri-Cities. It’s also known as “The Heart of Washington Wine Country,” with more than 160 wineries. However, according to Gallup, the region has one of the highest obesity rates in the country — at 33.2 percent — which shows an increase from the 31.5 percent obesity rate a CDC survey found for the area in 2010.

8. Topeka, Kansas

Obesity rate: 33.3 percent

Annual obesity-related costs: $109.8 million

More than 42,000 of the 127,473 residents of Topeka, Kan., suffer from obesity, according to data from Gallup. The good news is the city’s situation appears to be improving: Topeka had an obesity rate of 36 percent in 2010, almost three percentage points above where it is today, according to the CDC survey.

Topeka, the capital of Kansas, was also named as one of the 10 best cities for the next decade by Kiplinger’s Personal Finance Magazine in 2010.

7. Lakeland-Winter Haven, Florida

Obesity rate: 33.5 percent

Annual obesity-related costs: $279.3 million

According to Gallup, the Lakeland-Winter Haven, Fla., metro area has the potential to save more than $154 million in health-care costs if its obesity rate dropped to 15 percent. Instead, 33.5 percent of its residents suffer from obesity, racking up more than $279 million a year in medical bills.

The metropolitan area, which includes the cities of Lakeland and Winter Haven, has more than 75 lakes and is located in central Florida between Orlando and Tampa. In 2010, 37.9 percent of its residents were obese, according to the CDC study.

6. Charleston, West Virginia

Obesity rate: 33.8 percent

Annual obesity-related costs: $146.9 million

Charleston is the capital of West Virginia and is dubbed the cultural, recreational and business capital of the Appalachian Mountains. It’s home to several golf courses and parks, including the Haddad Riverfront Park along the Kanawha River.

There are more than 51,000 people living in the city, as of the 2010 census, and based on the rates from Gallup approximately 17,000 of them are obese. In addition, about 17 percent of the population has also reported having diabetes.

The Gallup-Healthways’ number is up from the CDC survey’s obesity rate of 32.3 percent for the city in 2010. According to the CDC, the state of West Virginia had a 32.5 percent obesity rate in 2010, placing Charleston higher than the state average.

5. Beaumont-Port Arthur, Texas

Obesity rate: 33.8 percent

Annual obesity-related costs: $182.8 million

Located in southeast Texas, this metro area includes the cities of Beaumont and Port Arthur. Oil is big business for the region, with refineries throughout the area. The metro area has been a major player in the oil industry ever since the Lucas Gusher exploded on Spindletop Hill in 1901.

According to the Gallup-Healthways Well-Being Index, the metro area could potentially save $101.6 million in medical costs if its obesity rate dropped to 15 percent, instead of the almost 34 percent it has now. Beaumont-Port Arthur is the second most obese metro area in Texas, which has a statewide obesity rate of 31 percent.

4. Rockford, Illinois

Obesity rate: 35.5 percent

Annual obesity-related costs: $179.4 million

Located in northern Illinois, Rockford calls itself the “City of Gardens” because of the 7,000 acres of parks, trails, tree-lined streets and public gardens within its borders. That’s not the only nickname the city has had — it has also been called “Forest City,” because of its woods and was once known as the “Screw Capital of the World” due to factories that produced screws and bolts. Manufacturing is still the area’s biggest industry.

Rockford also ranks as the fourth fattest city in the country, however, with an obesity rate of 35.5 percent. Of the more than 152,000 people who live in Rockford, nearly 54,000 are considered obese, while 10 percent have diabetes and 23 percent live below the poverty line.

3. Huntington-Ashland, West Virginia-Kentucky-Ohio

Obesity rate: 36 percent

Annual obesity-related costs: $146.9 million

The Huntington-Ashland metropolitan area encompasses three states — West Virginia, Kentucky and Ohio — at the point where they all meet by the Ohio River.

The metro area first gained national attention in 2008 after an Associated Press story called it the nation’s unhealthiest. That led Jami Oliver to bring his ABC reality show, “Jamie Oliver’s Food Revolution” into Huntington, W.Va., to give schools and the town a nutrition make-over. Oliver has called his time there a success. However, the larger metro area still appears to be struggling — 36 percent of its citizens are obese, according to the Gallup-Healthways Well-Being Index, and nearly 20 percent suffer from diabetes.

2. Binghamton, New York

Obesity rate: 37.6 percent

Annual obesity-related costs $131.5 million

In the city of Binghamton, more than 17,000 residents are obese, according to rates from the Gallup-Healthways Well-Being Index. It's surprising then that 54 percent of respondents also said they exercise frequently.

Located at the junction of the Susquehanna and Chenango rivers in southern New York, Binghamton has the highest obesity rate in the state, compared to New York State’s rate of just below 24 percent. Meanwhile, 27.8 percent of Binghamton’s population lives below the poverty level.

1. McAllen-Edinburg-Mission, Texas

Obesity rate: 38.8 percent

Annual obesity-related costs: $410.9 million

Located near the Mexican border in southern Texas, this metro area is the most obese in the nation, according to the Gallup-Healthways Well-Being Index. If the region dropped the rate from 38.8 percent to 15 percent, it could potentially save a whopping $252 million a year in medical costs annually. That’s a big savings, especially considering 50 percent of residents report being uninsured.

In 2010, 33.3 percent of the McAllen-Edinburg-Mission metropolitan area’s population was obese, according to a CDC survey, so the data suggest that the country’s most obese city is also getting worse, bucking the nationwide trend of stabilization in obesity rates.

See the full list: America's fattest cities

 “Fat & Fatter” premieres Thursday, March 29 at 9 p.m. ET, with a re-air Sunday, April 1 at 10 pm ET.

The Gallup-Healthways Well-Being Index results are based on telephone interviews throughout 2011, with a random sampling of 353,492 adults living in the U.S. Health-care costs were based on the National Institute of Health’s estimate of $1,429 per person, per year, in additional health-care costs for people considered obese, compared to those of non-obese individuals.

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