American waistlines keep growing

There's now scientific evidence to back up the notion that Americans are developing bigger waistlines. According to a new study, published in JAMA, the average waist circumference in the U.S. grew by an inch between 1999 and 2012.

These findings contradict previous data from the National Health and Nutrition Examination Survey (NHANES) which found that no major changes in obesity occurred between 2003 and 2012. Centers for Disease Control (CDC) researchers used the same survey as a source, but determined that the average waist size expanded from 37.6 inches at the beginning of the study to 38.8 inches at the end.

Using seven different two-year cycles of NHANES data, researchers analyzed 32,816 men and non-pregnant women ages 20 and older. Abdominal obesity, defined as a waist circumference larger than 40.2 inches for men and larger than 34.6 inches for women, increased overall from 46.4 percent to 54.2 percent. Men had a 0.8-inch waist circumference increase and 6.4 percent abdominal obesity increase overall. Women had a 1.5-inch waist circumference increase and 9.3 percent abdominal obesity increase overall.

Non-Hispanic white people had an increase of 8 percent in abdominal obesity, non-Hispanic black people had an increase of 8.5 percent and Mexican-Americans had an increase of 9,3 percent.

While it’s not clear why this increase is happening, the researchers recommended doctors continue to measure waist circumference as a measure to preventing and managing obesity in patients. Eating healthy, portion control and regular exercise can help reduce abdominal obesity.

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