While adult obesity rates haven’t changed, some children are seeing the benefits of a nation focused on slimming down.

More than a third of Americans are still obese. But as a group, children ages 2 to 5 are slowly getting fitter, according to a new report from the U.S. Centers for Disease Control and Prevention (CDC).

In the 2003–2004 time period, nearly 14 percent of those children were obese. That number declined 43 percent to just over 8 percent in 2011–2012.

Dr. Tom Frieden, director of the CDC, said obesity-prevention programs in communities are helping these young children. For example, federal nutrition programs have created a significant decline in obesity prevalence among low-income children aged 2 to 4 years old.

“This confirms that, at least for kids, we can turn the tide and begin to reverse the obesity epidemic,” he said.

Reducing childhood obesity and improving the nation’s health have been pet causes for First Lady Michelle Obama.

“I am thrilled at the progress we’ve made over the last few years in obesity rates among our youngest Americans,” she said in a press release. “With the participation of kids, parents, and communities in Let’s Move! these last four years, healthier habits are beginning to become the new norm.”

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While the very young are getting healthier, the rates of obesity in other children and adults remain unchanged.

Obesity prevalence in children remained at 16.9 percent. For adults, the rate is 34.9 percent. In children, obesity is defined as a body-mass index (BMI) above the 95th percentile for age growth charts. For adults, obesity means having a BMI over 30. For example, a 6’0” person weighing 222 pounds or more would be considered obese.

Dr. Mark Berman, a physician with One Medical Group, said while it’s good that obesity rates aren’t rising, there’s a lot more work to be done.

“Collectively, we will not make a big dent in obesity until we shift our cultural notion of a ‘proper meal’ to match the reality of our sedentary and technology-assisted lifestyles,” Berman said. “This means shifting the focus of our diets away from highly refined grains and calorie-dense animal products, towards more nutrient-dense, plant-based foods.”

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To change our health, Berman says we must face the uncertainty and discomfort of changing habits collectively and with strong support in the healthcare setting and beyond.

“Our brains are wired to be social, not autonomous. Habits are strongly influenced by culture, what our friends and loved ones do, and the way our physical world is architected,” he said. “So if our physical and cultural environment gears us to live a certain way, it takes tremendous skill, commitment and energy to live a different way.”

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