An unhealthy cholesterol level, once a condition thought to be isolated to the middle-aged and elderly, is increasingly becoming a problem among the young. The problem is even greater than many health experts realized. A nationally representative survey of blood test results in American teenagers found that more than 20 percent of those aged 12 to 19 had at least one abnormal level of fat. The rate jumped to 43 percent among those adolescents who were obese.

The study, published in the CDC's Morbidity and Mortality Weekly Report, analyzed data collected from 3,125 teens through the National Health and Nutrition Examination Survey conducted every two years. The percentage of teens with an abnormal blood lipid level varied by weight, ranging from 14.2 percent of those whose weight was normal to 22.3 percent among those who were overweight to 42.9 percent among those who were obese.

Previous studies have shown that adolescent obesity is more often than not accompanied by an increase in a host of health problems in youths that were previously found mostly among adults, including high blood pressure, diabetes and arthritis. The new data detail obesity's effect on cholesterol levels, which can increase the risk for a variety of illnesses, including diabetes and heart disease.

"People are worried that this generation is going to grow up to have more cardiovascular disease than the current generation," said Denise Simons-Morton of the National Heart, Lung and Blood Institute in an interview with the Washington Post. "This problem is poised to negate all of the advances we've made in cardiovascular health."

1 in 5 teens at risk of heart disease
Federal survey finds 20% of American teens have a cholesterol level that puts them at risk for heart disease.