ATLANTA — Americans are getting more apple-shaped, packing inches onto their middles even amid signs that the torrid pace of weight gain nationally has slowed.
People whose fat has settled mostly around their waistlines instead of in their hips, thighs, buttocks or all over are known to run a higher risk of heart disease, diabetes and other obesity-related ailments, according to a government study released Tuesday.
The average U.S. waist circumference steadily increased to 38.8 inches in 2012, up more than 1 inch in about a dozen years, according to a study from the U.S. Centers for Disease Control and Prevention. Almost two in three women in the U.S. had abdominal obesity by the end of the study, up from 55 percent, as did 43.5 percent of men. The biggest increases in waistlines were among Mexican-Americans, blacks and women.
“The increase is a concern. There’s no question about that,” said Dr. William Dietz, an obesity expert formerly with the CDC and now at George Washington University.
The number of obese Americans based on weight and height didn’t change significantly during the same time period, according to the report, which was published in the Journal of the American Medical Association. It’s not clear what is driving the increase in abdominal obesity, although poor sleep, certain medicines and chemicals that disrupt the body’s endocrine system may play a role, the researchers said.
“We have some signs that things may be stabilizing,” said Earl Ford, the lead researcher and a medical officer at the CDC. “We have to just watch it for a couple more cycles to know where we stand and if we have turned the corner on obesity. It’s a little early in the game yet.”
Measuring one’s waist is an easy way to estimate how much fat has taken hold in the abdomen, the most worrisome location for excess pounds, according to public health officials. The so-called visceral fat is found around the internal organs and has been identified as a major contributor to heart disease.
The researchers analyzed national surveys of health and nutrition taken by 32,816 people from 1999 through 2012. Women added 1.3 inches during that time, with an average waist span of 37.8 inches in 2012. Women are considered to have abdominal obesity when their waist is larger than 34.6 inches.
Men didn’t have to let their belts out quite as far, adding less than an inch to yield an average waist size of 39.8 inches at the end of the study. Abdominal obesity is triggered in men with a waist circumference of greater than 40.2 inches.
About 79 million American adults are obese, according to the CDC.
The Food and Drug Administration last week approved a new weight-loss pill from Orexigen Therapeutic, the third new obesity drug cleared for the U.S. market within the past two years.
The Associated Press contributed to this report.
