Obesity prevalence still high in the US, but may be leveling off
MedWire News: The prevalence of obesity among US adults, children, and adolescents is still high, but has changed little in recent years, report researchers.
The findings arise from two studies, published in JAMA, that analyzed data from the 1999-2008 and 2009-2010 National Health and Nutrition Examination Surveys (NHANES).
In the first study, Katherine Flegal (Centers for Disease Control and Prevention, Hyattsville, Maryland, USA) and co-investigators estimated the prevalence of adult obesity, defined as a body mass index (BMI) of 30 kg/m2 or more, in 2009-2010 and compared the results with data from 1999 through 2008.
The age-adjusted prevalence of obesity in 2009-2010 was 35.7% among men and 35.8% among women.
There was no significant increase in the prevalence of obesity over the 12-year period (from 1999 through 2010) among women overall. Significant increases were observed for non-Hispanic Black and Mexican-American women, however, and for men there was a significant linear increase in the prevalence of obesity from 1999 through 2010.
Of note, among both men and women, the prevalence of obesity during the most recent 2 years (2009-2010) and the previous 6 years (2003-2008) did not differ significantly.
"These data suggest that the increases in the population prevalence of obesity previously observed may not be continuing at a similar rate, and in fact, the increases appear to be slowing or leveling off," say Flegal et al.
In the second study, Cynthia Ogden (National Center for Health Statistics, Hyattsville, Maryland, USA) and team analyzed NHANES data and estimated the prevalence of obesity among US children and adolescents over the same 12-year period.
They report that in 2009-2010, 16.9% of children and adolescents (aged 2-19 years) were obese (BMI ≥95th percentile of the BMI-for-age growth charts).
There was a significant increase in obesity prevalence between 1999-2000 and 2009-2010 in males aged 2-19 years, but not in females. Similarly, trends in BMI indicated a significant increase among adolescent males but not females.
However, there was no change in obesity prevalence between 2007-2008 and 2009-2010 for both males and female adolescents.
The authors say that the prevalence of obesity among children has been suggested to reach 30% by 2030. However, "the data presented herein suggest that the rapid increases in obesity prevalence seen in the 1980s and 1990s have not continued in this decade and may be leveling off."
They conclude: "More research is needed to understand why these changes may be occurring."
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By Nikki Withers