The US obesity rate for adults has climbed to 37.7%, up from 32.2% 10 years ago, according to a report released Thursday by the Centers for Disease Control and Prevention (CDC).

And after nearly a decade of women and men having similar rates, women now have higher rates (38.3% vs 34.3%), said lead author Cynthia L Ogden, PhD, from the CDC's National Center for Health Statistics.

In 2003–2004, 33% of women were obese compared with 31% of men, but the differences weren't statistically significant, she told Medscape Medical News.

No difference in obesity rates between genders was seen in children and teens in the latest numbers.

"It's very worrisome," Bartolome Burguera, MD, PhD, endocrinology specialist at Cleveland Clinic in Ohio, said of the new report. "We thought the situation was plateauing," he told Medscape Medical News.

Among the few neutral trends in the data gathered from 2011–2014 are the fact that the rate for youth obesity appears to have stayed steady. No changes were seen from 2003–2004 through 2013–2014 for ages 2 to 19.

However, the data show that nearly 9% of preschoolers, 17% of kids aged 6 to 11, and 20% of teens are obese.

Concerning Data From Some Ethnic Groups and Women

Dr Ogden and colleagues used data from National Health and Nutrition Examination Surveys (NHANES), which are the gold standard, she said, since self-reports tend to overestimate height and underestimate weight. NHANES data contain the actual measurements.

Obesity is defined using body mass index (BMI) calculated from height and weight, and a BMI of 30 kg/m2 or higher is considered obese. As an example, someone 5 feet 9 inches who weighs at least 203 pounds would be considered obese, with a BMI of 30.

Sorted by race, the numbers indicate prevalence of obesity from 2011-2014 was lowest among non-Hispanic Asian adults (11.7%), followed by non-Hispanic white (34.5%), Hispanic (42.5%), and non-Hispanic black (48.1%) adults.

Non-Hispanic black women had the highest prevalence of obesity, at 56.9%, up from 53% 10 years ago.

Dr Burguera said he was particularly concerned about the high numbers among some minority populations.

"That brings up the issue of economics — eating healthily, having access to a gym, having a safe place to exercise….We know that sleep is also playing a big role. When you have a complicated life, eating healthy and taking care of your life to some degree becomes secondary," he said.

High numbers among Hispanic and black women relative to their male counterparts are driving the higher numbers of women overall who are obese, Dr Ogden explained.

She points to the differences between African American women and men (56.9% vs. 37.5%, respectively) and Hispanic women and men (45.7% vs 39%, respectively). For non-Hispanic whites, the rate is 35.5% (women) vs 33.6% for men.

By age, men 40 to 59 (38.3%) had a higher prevalence of obesity than men ages 20 to 39 (30.3%). Women ages 40 to 59 (42.1%) had a higher prevalence of obesity than women ages 20 to 39 (34.4%).

The latest numbers pull further away from the CDC's Healthy People 2020 goal of hitting an overall obesity rate of 30.5% in 5 years.

The overall rate of childhood obesity is now higher than the Healthy People 2020 goal of 14.5%, but the prevalence among children ages 2 to 5 years is just below the goal of 9.4%.

Education about healthy foods and activities at the youngest ages will be critical, Dr Burguera said, adding that changes in food policy and more exercise in schools must be a priority.

"Children are getting heavier very fast. And we know that a heavy kid will most likely be a heavy adult," he concluded.

Dr Ogden and Burguera have no relevant financial relationships.

CDC report