By Rebecca Sharim Storace, M.D.:

Obesity in America is a growing problem, and not just in adults. More than a third of the children and adolescents in the United States are overweight or obese, according to 2010 data from the U.S. Centers for Disease Control and Prevention. And since 1980, the number of obese children and adolescents has almost tripled, a jump attributed in part to poor food choices and insufficient physical activity.

Despite the ballooning problem, parents and doctors often find the topic of childhood obesity difficult to discuss. To start the conversation, ABC News' chief health and medical editor Dr. Richard Besser hosted a Twitter Chat on the subject Tuesday. Experts from the CDC, the National Institutes of Health, and the American Academy of Pediatrics, as well as clinicians, parents and others with personal experience joined in the one-hour discussion.

Here, some of the highlights.

The Risks Are Overwhelming

"Childhood obesity affects every organ system in the body," tweeted Dr. Seema Kumar, the director of the Pediatric Weight Management Program at Mayo Clinic.

The risks include diabetes, high blood pressure, and high cholesterol. In fact, roughly 70 percent of obese youth are thought to have at least one risk factor for heart disease, according to the CDC. What's more, experts agree that obese youth are at high risk of becoming obese adults, prompting even more health problems, including joint disease, heart disease, sleep apnea and certain cancers.

The health risks of obesity are not only physical, they're psychological as well. Childhood obesity has been linked to depression, anxiety and poor self-esteem.

"Overweight children are also more likely to be bullied," tweeted Thomas McInerny, president of the American Academy of Pediatrics.

Schools, Government Play a Critical Role

Tweeters agreed that it would be beneficial if the government funded programs to promote healthy food choices, rather than pay the heavy consequences of obesity in the future.

"Obesity costs $7.6 billion/yr in NY," tweeted Montefiore Medical Center.

New York City Mayor Michael Bloomberg's proposed ban on super-sized sugary drinks was shot down Monday just before going into effect. But some Twitter chat participants still strongly support the move to limit these drinks.

"Sugary drinks are a major source of empty calories and contribute to kids gaining weight," tweeted James Marks, senior vice president and director of the Robert Wood Johnson Foundation Health Group.

Schools need to do their part to ensure that children are making healthy choices, some experts said. On top of offering healthy choices in the cafeteria, schools also need to pay attention to snacks and class parties, according to Angela Haupt, health and wellness editor for U.S. News and World Report.

"48 student birthdays = 48 cupcakes at 300 calories a piece = 14,400 extra calories/year," she tweeted.

Educating kids about nutrition is also important.

"I'd love it if school tied in lessons - learning about calories in science, math, PE and home economics! Apply in cafeteria!" tweeted @FatGirlvsWorld.

Prevention Is Easier Than Treatment

Preventing obesity is essential, experts said, as treating obesity is extremely difficult. It's important to promote healthy food choices and physical activity.

"Lack of exercise is [a] big risk factor for being overweight," McInerny tweeted. "Need at least 1hr [of]exercise 5 days/wk."

McInerny also shared the 5-2-1-0 formula: 5 fruits and vegetables; less than 2 hours of screen time; 1 hour of exercise; and 0 sugary drinks.

Parent support is also critical. Healthy food choices and regular physical activity should be promoted as a lifestyle, not a diet. Experts encouraged parents to sit down with their kids for meals and involve kids in food shopping and preparation. And because parents are role models for children, they need to be conscious of their own eating and activity patterns.

You can find the transcript of Tuesday's chat here.

Our next chat is Tuesday, March 19 at 1 p.m. ET. We'll be discussing concussions. Joining in is easy. Click here for the details!