In spite of recent declines in obesity among younger children, the number of youth who are overweight or obese still remains high.

Given the persistence of obesity in the United States — and many other countries in the world — can anything be done to reverse an epidemic that has taken years to develop?

Obesity is a problem that has enormous influence on a person’s overall health and wellness. It’s linked to several health issues, including heart disease, diabetes, and certain types of cancer.

Children who are obese are at a greater risk of becoming obese adults.

According to the U.S. Centers for Disease Control and Prevention, 17 percent of children and adolescents aged 2 to 19 years are obese. That’s about 12.7 million children. This rate has remained fairly stable for the past decade.

The U.S. is not alone in the obesity epidemic. Around the world, at least 41 million children under the age of 5 are obese or overweight, according to the World Health Organization.

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An Ounce of Prevention

Although the number of obese children has held steady, preventing more children from becoming overweight makes for a better strategy than treating them later on.

“Once overweight or obesity sets in, and a child is carrying a larger amount of weight and adipose tissue, it’s very hard to reverse that,” Christina Economos, an associate professor at the Friedman School of Nutrition Science and Policy at Tufts University, told Healthline. “It’s quite persistent.”

Healthy eating and physical activity are the cornerstones of maintaining a healthy weight.

However, many other factors contribute to obesity among children, including school and community environments, exposure to food advertising, and lack of access to affordable healthy foods.

These factors can vary greatly among communities and even among families within the same community. Because of this, an equally varied approach to preventing obesity is more likely to deliver the most sought-after results.

“It’s unlikely that one specific, either program or policy, will have the impact that we want,” Economos said. “It will actually take a lot of different strategies targeting multiple environments that the children move through.”

These environments include the children’s schools, homes, and communities.

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Holistic Approach to Obesity

There has long been a healthy eating and physical activity component to school curriculum. But many schools now take a holistic approach to preventing obesity among children.

These programs often involve partnerships with other schools, universities, and non-profits. They attempt to teach children how to live healthy lives even when tempted by unhealthy options.

“It’s an uphill battle. You have to work hard. You have to be a positive deviant in a tough environment to be healthy,” Economos said. “We want to really change that so the healthy option is the easy option.”

Programs vary, but often focus on increasing physical activity, improving eating habits — eating less fat and more fresh fruits and vegetables — and decreasing the time children spend using electronic devices.

Programs may also work to improve playground facilities, add more after-school activities for children, or make school meals — especially breakfast — healthier.

What works depends on the specific school and the age of the children.

Economos focuses mainly on elementary school children and their specific daily routines.

“They spend a lot of their day in school and then in after-school programs,” she said. “So those are two areas that I’ve spent a lot of time developing initiatives within.”

But even children who spend a lot of time at school eventually go home or out into the community.

So some school-based programs try to include parents and community members in the activities. This can range from healthy living marketing to nighttime cooking classes at the school for families.

They may even involve the local businesses in healthy living.

“We have a restaurant initiative for when children eat out,” Economos said, “to try to reduce the total calories that they consume by helping to provide healthier options throughout the restaurant industry.”

In underserved neighborhoods, programs may also target the corner markets where children often buy their food. This highlights the need to tailor programs to the specific community.

“There are different sets of strategies when you’re trying to reach deep into underserved communities,” Economos said. “The last thing we want is to develop strategies that are blanketing the country but are only reaching those children who are in better-resourced areas.”

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Obesity Prevention Over the Long Run

Studies of obesity prevention programs for children show mixed results. Some reviews of this research have found modest benefits.

Although obesity rates have reached a plateau for children of many ages, there is still progress among preschool children, according to Economos. This gives clues to what is working.

“When we see a decline happening in our youngest children — the 2- to 5-year-olds — we look to programs that have been really working hard over the last decade,” she said.

The decline, though, is not the result of a single program. Economos points to multiple efforts targeting this age group. This includes the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), greater promotion of breastfeeding, and other programs.

More importantly, even this slight decline was the result of a lot of effort over a long period of time. For some people, this may be discouraging, but Economos sees hope in even the smallest shift.

“I wouldn’t want to see people abandon the cause because progress isn’t as fast as people had hoped,” Economos said. “In the public health world, it’s actually going really well.”