New signs of improvement in the youth obesity epidemic?

There's more evidence to suggest the USA's epidemic of childhood obesity is stabilizing, and the reasons may be that kids are eating better and watching less TV.

Between 2001 and 2009, U.S. adolescents increased physical activity, ate more fruits and vegetables, ate breakfast more, watched less TV and ate fewer sweets, a new study says.

"It's only recently, in the past decade, that some studies have begun to see some leveling off" in obesity-related behaviors, says Ronald Iannotti, chairman of the department of exercise and health sciences at the University of Massachusetts in Boston and co-author of the study in October's Pediatrics, online Monday.

"Seeing this pattern is very encouraging," he says. They worked with kids as young as 11, he adds, and saw the trend "in younger kids as well."

Iannotti and co-author Jing Wang did the research while with the Eunice Kennedy Shriver National Institute of Child Health and Human Development in Bethesda, Md.

They analyzed data from a nationally representative sample of 35,000 U.S. students, ages 11 to 16, collected in 2001, 2005 and 2009 about their diets, physical activity, and height and weight, which was used to calculate where they fall on Body Mass Index (BMI) growth charts.

The average BMI percentile increased over the nine years, but the significant change occurred from 2001 to 2005. The average BMI percentile declined from 62.33 in 2005 to 62.07 in 2009 (both in the normal range). Children are considered overweight if they fall between the 85th to 95th percentile on BMI growth charts. Kids fall into the obese category if they are at or above the 95th percentile on charts. This means their BMI is larger than 95% of the reference population, a group of children from the 1970s and '80s.

Where "we had been seeing an increasing trend (in BMI percentile), we don't see that between 2005 and 2009," says Iannotti.

In the study, most adolescents fell far short of the recommended 60-plus minutes a day of physical activity seven days a week, but the number of days they got that amount increased significantly between 2001 and 2009, from 4.33 to 4.53.

Consumption of fruits increased from an average of two to four days a week in 2001 to five or six in 2009; vegetables from an average of two to four days a week to almost five. Sugary soft drink consumption declined from almost five drinks a day to about four. The average number of days a week they ate breakfast increased from 2.98 to 3.25.

"Over the previous decades, the pattern had been that kids were getting less physical activity, and it's been very hard to increase their fruit and vegetable consumption," Iannotti says. "We've got a long way to go, but the good news is that those are increasing." Among other findings:

• Boys reported getting more physical activity than girls but also playing more video games and watching more TV. Overall, there was a decrease in time spent watching TV, the most prevalent sedentary behavior.

• Girls logged more computer time for social media, homework and Internet use.

• Girls ate more fruits and vegetables than boys, but also more sweets and fewer breakfasts.

The study suggests that pediatricians may need to do more to tailor health advice to teens based on gender, Iannotti says.

These findings are consistent with other recent studies, "including results from numerous cities and states indicating some initial declines in the prevalence of childhood obesity," says Melissa Laska, an associate health professor at the University of Minnesota. She was not involved in the study.

"We may be beginning to see the results of our comprehensive efforts at many levels — in schools, communities, clinical care settings and beyond — but there is still much work that needs to be done," she says.