Given the upward trend, "it will be difficult for us as a country to achieve the 15 percent," Deb Galuska, associate director for science in the CDC's division of nutrition, physical activity and obesity, told ABCNews.com on Thursday.
"The epidemic of adult obesity continues to rise in the United States, indicating that we need to step up our efforts at the national, state and local levels," said Dr. William Dietz, director of CDC's division of nutrition, physical activity and obesity in a Thursday statement. "We need to encourage people to eat more fruits and vegetables, engage in more physical activity and reduce the consumption of high-calorie foods and sugar-sweetened beverages in order to maintain a healthy weight."
To assess Americans' efforts to fight obesity, the CDC collected information by asking more than 350,000 people about their height and weight. As a result, officials said it's possible the latest obesity rates are even higher than reported.
"When you ask people their weights, they tend to underestimate," Galuska said. "When you ask people their heights, men in particular, tend to overestimate."
"What we think in the survey is that it's a conservative estimate," she added.
America's Most Overweight States
Though Americans still have time to meet the national goal to reduce obesity, some states have a ways to go.
The states with the biggest waistlines - Mississippi, Alabama and Tennessee - are all battling obesity rates of more than 30 percent.
CDC data revealed that other states with the dubious honor of being home to overweight residents include Louisiana, with a 29.8 percent obesity rate and West Virginia, at 29.5 percent. Clustered in the south, Arkansas, South Carolina, Georgia, Texas and Oklahoma weighed in next, with obesity rates upwards of 28 percent.
The CDC said Thursday that both behavior and demographics may play a role in those numbers. To trim down, the agency recommends people get at least 30 minutes of exercise each day and take actions like replacing high fat foods, desserts and sugary drinks with items like fruits and veggies and whole grains.
America's Skinniest States
On the flip side, Colorado comes closest to reaching the nation's goal of reducing obesity to 15 percent. Colorado had an obesity rate of 18.7 percent for 2007.
"Colorado is a state where there are a lot of possibilities for physical activity, with parks and the Rocky Mountains and the trails and stuff there," Galuska said.
Not one other state has an obesity rate of less than 20 percent. Still, those states where people stay trimmer than most include Connecticut, Vermont, Massachusetts, Hawaii, Rhode Island, Utah, Montana and Washington, D.C. In those places, obesity rates ranged between 21.2 and 21.8 percent, respectively.
