By Jonathan Easley - 03/04/14 09:34 AM EST
Mississippi and West Virginia are the most obese states in the country, according to a Gallup survey released on Tuesday.
Delaware, Louisiana, Arkansas, South Carolina, Tennessee, Ohio, Kentucky and Oklahoma round out the top 10 most obese states.
The poll also found a larger percentage of people nationwide are obese.
In 2012, only five states registered more than 30 percent obese, but now, every state in the top ten has surpassed that mark.
Gallup first began tracking obesity rates in 2008, when the national average was 25.5 percent. The national average is now 27.1 percent
High rates of obesity add to the nation's health costs, Gallup noted.
“As the rate of obesity among U.S. adults continues to increase across all 50 states, health issues and costs associated with the chronic diseases that can accompany obesity will continue to rise,” Gallup said. “Gallup-Healthways Well-Being Index data show Americans are not eating as healthily or exercising as often as in past years, which might play a role in the increase of national and state obesity rates.”
It said people with obesity are "more likely to report having had a diagnosis of chronic disease at some point in their lives, including high blood pressure, high cholesterol, depression, diabetes, cancer and heart attacks.
Gallup defined people as obese if they had a body mass index of higher than 30. The index is based on a person's height and weight.
Montana and Colorado lead the way for least obese states. About 2-in-10 people in those states are obese.
Nevada, Minnesota, Massachusetts, Connecticut, New Mexico, California, Hawaii and New York are also among the lease obese states in the country.
The Gallup-Healthways Well-Being Index survey of more than 178,000 adults was conducted between Jan. 2, 2013 and Dec. 29, 2013. The margin of error for most states is 2 percent, but could be as high as 4 percent for states with small populations.