New research indicates that many U.S. children as young as 13 may have risk factors for type 2 diabetes, the form of the disease once considered a problem of older adults.

In addition, 41 percent had elevated blood sugar levels when tests were taken after a fast, while 36 percent had high levels of insulin, a hormone that helps process blood sugar. Higher-than-normal insulin and blood sugar levels signal that the body is becoming resistant to insulin, a precursor to type 2 diabetes.

Few children in the study had actual diabetes, but the level of risk factors was "very high," said study co-author Dr. Francine Kaufman of Children's Hospital Los Angeles.

The study included a large number of Hispanic and Native American children -- ethnic groups that have a particularly high rate of type 2 diabetes -- and these students had the highest fasting blood sugar levels.

Dr. Kaufman stated that, “The findings add to evidence that excess pounds and inactivity are putting more and more U.S. children, particularly minorities, at risk of diabetes.

"This really screams for us to do comprehensive prevention," she said.

That can include healthier foods and a return to physical activity at school, according to Kaufman, as well as efforts in the community -- like creating safe places for children to get some exercise -- and at home.