"It was just this much more to go and then I would have been diabetic," said David Duran, T.E.E.N.S. Program graduate.
Twenty percent of all youngsters in the U.S. are obese. And two-thirds will become obese adults, which may lead to hypertension, stroke and diabetes.
"It was just like the fear of diabetes. I didn't even know what it was but I knew it wasn't good," said David.
"It's important to focus on changing that behavior," said Daphne Bryan, MD, Virginia Commonwealth University.
Bryan runs the novel T.E.E.N.S. Program.
At-risk kids like David and their families meet with nutritionists and exercise scientists for two years.
Doctors say whole family education boosts immersion and drives home key lessons on health.
"The activity's just not there anymore. There's more screen-time than running and playing time," said Bryan.
To date, all graduates have lowered their cholesterol and blood pressure levels. Nationally, studies show 73 percent of similar programs have positive results.
"So I started coming in, and it was like, 'Hey, I lost a pound.' Next day it was like, 'Hey, I lost another one,'" said Melitza Duran, Teens Program graduate.
David's sister Melitza went from 216 pounds to 184 in two years.
"Feels like you can just take on the world, anything," said David.
David himself lost 47 pounds and staved off diabetes. He hopes this country's youngsters are paying attention.