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 8, 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 on 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 paediatric 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.