Aug. 3, 2010 -- More Americans are becoming obese. Obesity rates inched up 1.1% between 2007 and 2009, according to a new report released by the CDC.
In just the past two years, 2.4 million people have joined the ranks of the obese. About 72.5 million U.S. adults are now obese, the report found. That's 26.7% of the population, compared to 25.6% in 2007.
Some states are more affected than others, says Thomas R. Frieden, MD, MPH, director of the CDC, who presented the data at a teleconference Tuesday. "The number of states where self-reported obesity is 30% or higher has tripled, from three to nine."
In the latest tracking of obesity rates, the CDC used the 2009 survey data known as the Behavioral Risk Factor Surveillance System (BRFSS) to update estimates of national and state-specific obesity rates. The BRFSS is an ongoing state-based telephone survey conducted annually.
Respondents self-report weight and height, although researchers know men and women tend to overestimate height and women tend to underestimate their weight.
This year's survey results show that no state met the Healthy People 2010 target of reducing obesity to 15%, although some states did better than others.
Obesity is defined as having a body mass index or BMI of 30 or higher. A 5'8" person who weighs 200 pounds, for instance, has a BMI of 30.4.
Colorado, with 18.6% of residents obese, came closest to the Healthy People 2010 goal. Mississippi, with 34.4% of residents obese, did the worst.
While 33 states had obesity rates of 25% or more, nine of those had an obesity rate of 30% or more. In this bottom tier (in alphabetical order) are:
When researchers look at another data source, the NHANES (National Health and Nutrition Examination Survey), they find a higher percentage of the population -- 33.9% -- is obese. For that survey, height and weight are measured by researchers rather than self-reported.
"Obesity is common, serious, and costly; it affects every system in the adult body," says William Dietz, MD, MPH, director of the CDC division of nutrition, physical activity, and obesity, who also spoke at the teleconference.