What they survey shows is that the national obesity rate continues to climb, from 25.5 percent in 2008 to 28 percent in 2015.

Significant regional trends were also spotted. The rate is growing faster in the Midwest and South than in the Northeast and West, and in a sense, the nation is starting to divide along an obesity line.

The Midwest, where the rate is the highest, increased the most since 2008, by 3.2 percent to hit 30 percent last year. The West, meanwhile, which boasts the lowest rate now and historically, increased 1.8 percent since 2008 — and is now 5.4 percent lower than the rate in the Midwest. The Southern rate trails the Midwest by a mere .1 percent, and its rate has also been growing much faster (2.9 percent) than either than of the West or the Northeast (2 percent).

Related: 10 worst states for women

The surveyors said the cost that Americans pay for this trend is escalating right along with the obesity rate.

"Given that obesity is associated with illnesses such as heart disease, diabetes, stroke, osteoarthritis and some forms of cancer, the medical costs for an obese person amounted to $1,429 more per year than for a person of a normal weight, according to research conducted in 2008 by RTI International and the Centers for Disease Control and Prevention. After adjusting for inflation, the annual medical costs for 2015 are $1,573 more for a person who is obese than for a person of a normal weight," the survey reports.

Where should the battle against obesity be first launched? How about in the states with the highest rates, which are, as follows:

Both South Carolina and Kentucky are known for their own popular styles of barbecue, which can make it hard to diet in the two states. (Photo: iStock)

10. South Carolina and Kentucky (tie)

With 31.4 percent of their populations identifying as obese, these two gems of the South showed up in a dead heat in the last position. That said, South Carolina may have the larger challenge of the two. It also placed No. 8 on the list of states with the highest increases between 2008 and 2015 — a 3.8 percent hike. Kentucky did not make that list. Whew.

While delicious, lobster rolls and clam chowder aren't exactly healthy food staples. It's no wonder that Maine, known for some of the best seafood in the country, is a top state with high obesity rates. (Photo: iStock) 

8. Michigan and Maine (tie)

Another tie, this time among a couple of northern states. Sadly, both states — standing at a 31.5 percent obesity rate —are experiencing rapid increases compared to where they stood in 2008. Maine tops the list of the fastest-growing rate, with a 6.6 percent increase, while Michigan anchors the No. 6 position on that list with a 4.8 percent increase.

Yes, Cincinnati chili — a Mediterranean-spiced meat sauce for pasta and hot dogs — is a thing in Ohio and might be one reason behind its ranking on Gallup's list. (Photo: iStock) 

6. Ohio 

The Buckeye State represents a breaking point in this heaviest of the heavy list at 31.6 percent. There's actually little difference between this first group — a matter of just .2 percent separating No. 10 from No. 6. After this, though, the numbers take a jump and, with one exception, they are all southern states.

Mike Huckabee, who was governor of Arkansas from 1996 to 2007, has been very public in his battle with obesity. He once weighed as much as 300 pounds before he was diagnosed with type 2 diabetes, which prompted him to change his diet and begin excercising. He has used his profile to become a crusader for good health. (Photo: iStock)

5. Oklahoma and Arkansas (tie)

Such close neighbors, in so many ways, yet Oklahoma separates itself from the home of former President Clinton by placing No. 4 on the list of states with the greatest increases since 2008, at 5.5 percent. Arkansas does not appear on this list at all, so perhaps it's going in the right direction. Still, both Oklahoma and Arkansas are in the top five of Gallup's survey with a 33.5 percent obesity rating.

America's forefathers probably didn't anticipate one of the country's most historical states to make the most obese list. (Photo: iStock) 

3. Delaware

Only five U.S. states have a smaller population than "The First State," so nicknamed because its representative was the first of the original 13 states to sign the U.S. Constitution. So perhaps its rate (33.8 percent) can be more heavily influenced by the influx or outflow of just a handful of very heavy or very thin individuals. It is not on the list of states whose rates have increased the most since 2008.

One of the state's most recognized celebrities, Elvis Presley, famously struggled with weight problems before his death. (Photo: iStock) 

2. Mississippi

Gallup and Healthways offer estimates of the annual health care cost per 100 residents of obesity by state. Mississippi (35.5 percent) is No. 2 on this list, at $55.9 million. The estimated cost for all adults exceeds $1 billion. The only bright spot: It's not on the list of states whose rates have increased the most since 2008.

Apple butter is such a West Virginia staple that one weekend a year is dedicated to celebrate the sugary, spicy mixture. (Photo: iStock) 

1. West Virginia

The "Mountain State" faces substantial challenges if it hopes to give up its title as the most obese state in the country with 37 percent of its residents classified as obese. Not only is it statistically well ahead of Mississippi, but it ranks No. 2 (by .1 percent) on the list of states whose rates have increased the most since 2008, and No. 1 in terms of cost per 100 residents of obesity by state at $58.3 million. If those dedicated to reversing the obesity trend in America want a place to begin the search for the key, West Virginia would be a likely starting point.