A study posted online in JAMA on Wednesday indicates that in 2007-2008, the age-adjusted prevalence of obesity in the U.S. was 33.8 percent overall, with a prevalence of 32.2 percent among men and 35.5 percent among women. The corresponding prevalence estimates for overweight and obesity combined were 68 percent overall, 72.3 percent among men and 64.1 percent among women.

The study, which was conducted by the National Center for Health Statistics of the Centers for Disease Control and Prevention, also found that for women the prevalence of obesity showed no statistically significant changes from 1999 to 2008. For men there was a significant linear trend over the same period, but estimates from 2003 to 2008 did not differ significantly from each other.

Another NCHS study posted online in JAMA found no statistically significant linear trends from 1999 to 2008 in high BMI among girls and boys except among the very heaviest boys.