Less than one per cent of American teens are likely to need cholesterol drugs, says a new study that offers some reassuring news on the childhood obesity front.

Last year, the American Academy of Pediatrics issued eyebrow-raising new guidelines: doctors were urged to consider cholesterol drugs for more kids, even as young as eight, if they had high levels of "bad cholesterol," or LDL, along with other health problems like obesity and high blood pressure.

The academy didn't address how many children might fall into that category. Now, a new study published online Monday in the American Heart Association's journal Circulation helps allay concerns that "many, many" children might need to be on cholesterol drugs, said Dr. Stephen Daniels, lead author of the pediatric guidelines.

"The concern was, I think, because there's an increasing level in obesity, that it would lead to higher and higher cholesterol levels. They don't seem to be going up," he said.

The new pediatrics guidance was based on growing evidence that damage leading to heart disease begins early in life. At the same time, recent research has shown that cholesterol-fighting drugs are generally safe for children.

For the new study, researchers looked at data from about 10,000 children who took part in a national government health survey from 1999 to 2006. Of those, about 2,700 in the 12-to-17 group had LDL levels measured. About five per cent to seven per cent of these youth had elevated LDL.

Then the researchers checked those numbers against the pediatric academy guidelines, advising other factors that should be weighed in recommending medication. About 0.8 per cent fit the profile of those needing treatment with cholesterol-lowering drugs to ward off future heart problems. Based on 25 million Americans in that age group, the findings translate to about 200,000 young people.

"I think it provides some perspective on the issue," said lead study author Dr. Earl Ford, medical officer in the U.S. Public Health Service.

Exercise, diet remain key elements

Ford said that he'd noticed that after the academy guidelines came out last July, one thing missing from the debate was how many children might be affected.

"I think a lot of people thought large numbers of children were probably going to be put on medications for long periods of time," he said.

When total cholesterol levels — which include both LDL and "good" cholesterol, HDL — were measured for all ages, 6-17, researchers found that roughly 10 per cent had levels that were too high.

The study doesn't provide specifics for one of the more disturbing aspects of the new pediatrics guidelines: that some children as young as eight might need cholesterol-fighting pills. LDL readings for children under age 12 weren't available.

However, Ford believes the results from the older group probably apply to the younger children as well.

"This just confirms that it's a conservative set of recommendations," said Daniels, pediatrician in chief at Children's Hospital in Denver.

Cardiologist Dr. William Scott, a pediatrics professor at University of Texas Southwestern Medical Center, said that unless a child has a genetic predisposition to high cholesterol, regular exercise and an appropriate diet will help keep cholesterol in check.

"You really are empowered by your diet and activity," said Scott.