The waistlines of U.S. adults have continued to expand greatly over the last decade. Data from 1999 to 2012 show that the average, age-adjusted waist circumference increased from 95.5 centimeters in 1999-2000 to 98.5 centimeters in 2011-2012. Prevalence of stomach fat also increased from 46.4 percent in 1999-2000 to 54.2 percent in 2011-2012.
An earlier look at data from the same survey had suggested that the prevalence of obesity, calculated by body mass index, did not increase substantially between 2003 and 2012. But the new results run counter to that analysis, scientists argue September 17 in JAMA. Regularly measuring waist circumference might help prevent, control and manage obesity, they say.