NEW YORK (Reuters Health) – Cholesterol levels have improved slightly among American youth over the past two decades, according to government data released Tuesday.

From 1988 to 2010, the rate of high total cholesterol dropped from 11 percent to 8 percent in children ages 6 to 19, a report in the Journal of the American Medical Association shows.

“I think this is the first time we are seeing a real decline,” said Dr. Sarah de Ferranti, director of preventive cardiology at Children’s Hospital Boston, who wrote an editorial about the findings.

“The changes aren’t big, but if you look at the population level this is good news,” she added.

The levels of LDL cholesterol – also called “bad” cholesterol – and fats in the blood also fell among adolescents over the study, which is based on nationally representative data on more than 16,000 youths.

That would seem to bode well for today’s youngsters, whose risk of heart attacks and strokes down the road would be expected to drop in tandem with their cholesterol levels.

Unfortunately any potential benefit may be drowned out by the obesity epidemic, de Ferranti told Reuters Health. According to the U.S. Centers for Disease Control and Prevention, two-thirds of American adults and 15 percent of children are overweight or obese, and in some states the rate for children is above 30 percent.

“We haven’t really made big inroads there despite all the work we have been doing,” said de Ferranti. “We may reap some small benefits from improved cholesterol levels, but obesity is going to continue to lead to type 2 diabetes and heart disease in and of itself.”

The report, by Dr. Brian Kit at the Centers for Disease Control and Prevention in Hyattsville, Maryland, and colleagues, shows 22 percent of youths had either low HDL (“good”) cholesterol or high non-HDL cholesterol between 2007 and 2010. That is down from 27 percent in 1988 to 1994.

It’s not clear why the rates have been improving, especially given that obesity levels were on the rise during the study.

De Ferranti speculated that it could be that people are eating less fat, particularly trans fats, which have been linked to higher LDL and lower HDL cholesterol levels.

But instead of replacing the fat with vegetables and other healthy fare, it seems Americans have taken to high-carb products like sugary drinks, which still pile on the pounds.

“We may be trading one problem for another,” said de Ferranti.

TO SCREEN OR NOT

The new results come in the midst of a debate over whether or not all children should be screened for cholesterol problems.

Last year, the National Institutes of Health published guidelines saying all kids ages 9 to 11 should be screened for high cholesterol, whereas previous guidelines called for screening only in children with a family history of heart disease or high cholesterol.

But critics pointed out that routine screening would cost billions and lead many children to be treated with cholesterol-lowering drugs that have not been shown to cut their risk of heart disease later on.

“It is very unlikely that the advantage of starting a child on medication would justify the costs involved,” said Dr. Thomas B. Newman of the University of California, San Francisco, who has been critical of the new guidelines.

“Providing environments that make it easier for kids to exercise would be much more cost-effective,” he told Reuters Health, adding that portion sizes and government agriculture policies also need to be explored.

“Many unhealthy foods we consume in excessive amounts are cheaper because of government subsidies,” Newman said.

Newman and others have also criticized the many financial ties to drugmakers among members of the NIH panel that came up with the new screening guidelines.

De Ferranti said she wasn’t sure if universal screening is the answer, but that in the past, too few have been screened.

Doing more tests, she said, will help spot children with a hereditary type of high cholesterol, who would benefit from medication. And the dietary advice for dealing with cholesterol problems also depends on exactly which number is too high or too low, she added.

SOURCE: bit.ly/MvXYT6 Journal of the American Medical Association, online August 7, 2012.