CHICAGO - Roughly 2 million U.S. children ages 12 to 19 have a pre-diabetic condition linked to obesity and inactivity that puts them at risk for full-blown diabetes and cardiovascular problems, government data suggest.

Researchers from the federal Centers for Disease Control and Prevention and the National Institutes of Health examined the prevalence of abnormally high blood sugar levels after several hours without eating, a condition called impaired fasting glucose, or IFG, that is measured in a blood test.

One in 14 boys and girls in a nationally representative sample had the condition. Among the overweight adolescents, it was one in six.

Affected adolescents were more likely than those with normal fasting glucose measurements to have other symptoms suggesting they might be on the road to heart problems: Average levels of bad cholesterol and blood fats called triglycerides were higher in youngsters who had the pre-diabetic condition.