US Obesity Rates Hold Steady, But High: Study
Obesity rates in the United States remained stubbornly high over the past decade, with more than one-in-three adults and one-in-six children now considered obese, according to two studies published online this week in the Journal of the American Medical Association.
Among certain demographics, such as boys aged 6 to 19 years old, the rates of obesity (defined as a body mass index of 30 or greater) continued to climb during recent years, the researchers reported.
The studies include an analysis of CDC data from the 2009-2010 National Health and Nutrition Examination Survey (NHANES), which found that currently U.S. obesity rates among adults are comparable to those reflected in data from 1999-2008.
In 2009-2010, the age-adjusted average BMI was 28.7 for men and women, with an overall age-adjusted obesity prevalence of 35.7 percent.
Among men, the prevalence was 35.5 percent, and within race/ethnicity groups, prevalence ranged from 36.2 percent among non-Hispanic white men to 38.8 percent among non-Hispanic black men.
For women, the prevalence of obesity was 35.8 percent, and the range was from 32.2 percent among non-Hispanic white women to 58.5 percent among non-Hispanic black women.
Over the period from 1999 through 2010, obesity showed no significant increase among women overall, but increases were statistically significant for non-Hispanic black women and Mexican American women.
For both men and women, the most recent 2 years (2009-2010) did not differ significantly from the previous 6 years (2003-2008), the data revealed.
The age-adjusted prevalence of overweight and obesity combined (BMI 25 or greater) was 68.8 percent overall, 73.9 percent among men, and 63.7 percent among women.
“Obesity prevalence shows little change over the past 12 years, although the data are consistent with the possibility of slight increases,” the authors of the study wrote.
The examination of obesity among U.S. children and adolescents (birth through 19 years of age) included a representative sample with measured heights and weights from NHANES 2009-2010.
Among the measures analyzed were the prevalence of high weight-for-recumbent length (95th percentile or greater on the growth charts) among infants and toddlers from birth to 2 years of age and obesity (BMI 95th percentile or greater of the BMI-for-age growth charts) among children and adolescents ages 2 through 19 years.
The researchers analyzed trends in obesity by sex and race/ethnicity, and in BMI within sex-specific age groups every 2 years from 1999 to 2010.
The data revealed that among children and adolescents ages 2 through 19 years, 16.9 percent were obese in 2009-2010 and 31.8 percent were either overweight or obese.
The prevalence of obesity among males (18.6 percent) was significantly higher than among females (15.0 percent).
There was no difference in obesity prevalence among males or females between 2007-2008 and 2009-2010, but there was a significant increase in prevalence between 1999-2000 and 2009-2010 (per 2-year survey cycle) in male children and adolescents — but not in females.
“Significant differences in obesity prevalence by race/ethnicity were found. In 2009-2010, 21.2 percent of Hispanic children and adolescents and 24.3 percent of non-Hispanic black children and adolescents were obese compared with 14.0 percent of non-Hispanic white children and adolescents,” read the report.
The prevalence of high weight-for-recumbent length among infants and toddlers was 9.7 percent in 2009-2010. The prevalence did not change between 1999-2000 and 2009-2010. When the data from these time periods were analyzed together, there were significant differences by race/ethnicity, with Mexican Americans being significantly more likely to have high weight-for-recumbent length than non-Hispanic whites.
The researchers also found that there was a significant increase in BMI among adolescent males ages 12 through 19 years but not among any other age group or among females.
“Many efforts both at the national level and at state and local levels focus on reducing childhood obesity. Yet results from NHANES indicate that the prevalence of childhood obesity in the United States remains unchanged at approximately 17 percent; although increases in obesity prevalence may he occurring among males,” the researchers wrote.