New data examined from the National Health and Nutrition Examination Survey [NHANES; a nationally representative sample of the US population] suggests that the rate of increase for obesity in the US in recent decades may actually be slowing, although the rate of adult obesity remains high. The new study appears in JAMA.
The researchers examined the data from NHANES from 2007-2008 regarding trends in obesity and compared the results with data for 1999 through 2006. The study included an analysis of height and weight measurements from 5,555 adult men and women age 20 years or older. Overweight was defined as a body mass index (BMI) of 25.0 to 29.9. Obesity was defined as a BMI of 30.0 or higher.
“For women, the prevalence of obesity showed no statistically significant changes over the 10-year period from 1999 through 2008. For men, there was a significant linear trend over the same period, but estimates for the period 2003-2004, 2005-2006, and 2007-2008 did not differ significantly from each other. These data suggest that the increases in the prevalence of obesity previously observed between 1976-1980 and 1988-1994 and between 1988-1994 and 1999-2000 may not be continuing at a similar level over the period 1999-2008, particularly for women but possibly for men,” write the authors.
The study showed that in 2007-2008 the prevalence of obesity was 33.8% overall. Among men, prevalence was 32.2% overall and, within racial and ethnic groups, ranged from 31.9% among non-Hispanic white men to 37.3% among non-Hispanic black men. For women, the prevalence was 35.5%, and ranged from 33.0% among non-Hispanic white women to 49.6% among non-Hispanic black women. The prevalence of overweight and obesity combined was 68.0%, 72.3% among men, and 64.1% among women.
An Ongoing Epidemic
An accompanying editorial from J. Michael Gaziano, MD, MPH, of the Massachusetts Veterans Research and Information Center, Boston, cautions that while the studies in this issue of JAMA on the prevalence of overweight and obesity in the United States may offer some good news as far as trends, it is still a serious nationwide problem.
“But even if these trends can be maintained, 68% of US adults are overweight or obese, and almost 32% of school-aged US children and adolescents are at or above the 85th percentile of BMI for age. Given the risk of obesity-related major health problems, a massive public health campaign to raise awareness about the effects of overweight and obesity is necessary,” Gaziano writes. “The longer the delay in taking aggressive action, the higher the likelihood that the significant progress achieved in decreasing chronic disease rates during the last 40 years will be negated, possibly even with a decrease in life expectancy.”