Obesity in American children and teens is a problem that's only getting worse, according to a new study published in the International Journal of Pediatric Obesity.

Researchers at Baltimore's Johns Hopkins Bloomberg School of Public Health and National Institute on Aging in Bethesda, Md. found that over a 10-year period there has been a weight increase in children. But that increase was most significant in the heaviest 20 percent.

Researchers measured overall body mass index, waist circumference, and tricep skin thickness.

"Heavier children and adolescents gained more adiposity, especially waist size, and these findings were most significant among children ages 6-11," senior author Dr. Youfa Wang of The Johns Hopkins Bloomberg School said in a statement.

Researchers say that these teens are at risk for developing Type 2 diabetes and heart disease.

The study concluded that more effort needs to be made to understand different causes of increased obesity.