Ohio is ranked 12th on a list of the nation's most-obese states. The Gallup-Healthways Well-Being Index says nearly 30-percent of Ohio residents were obese in 2014. Last year, the group ranked Ohio 16th. Mississippi is ranked as America's most obese state, while Hawaii had the lowest obesity rate. The group says more than 66 percent of Americans are either overweight or obese, with a body mass index of 30 or greater. The national obesity rate is the highest it's been since Gallup began tracking the figures in 2008.