A new study suggests that high levels of cholesterol cannot be inferred in children who are obese, nor do children with normal body weights necessarily have healthy levels of cholesterol.

"We found, actually, that using body mass index to find kids with high cholesterol does not work well," said Dr Joyce Lee, a leader among the team of University of Michigan researchers who authored the study. "There were many overweight and obese kids who had normal cholesterol, and there were a fair number of healthy-weight kids who had high cholesterol."

Data from thousands of children nationwide were used to produce this study. Among factors looked at by the team were body mass index(BMI) overall cholesterol levels and the values for low-density lipoprotein (LDL) cholesterol, often referred to as bad cholesterol.

The American Academy of Pediatrics’ current cholesterol screening guidelines are based on BMI, but according to researchers, 50 percent of children with high cholesterol would go unscreened and 30 percent of obese children would be screened unnecessarily per these guidelines. According to the researchers, family history is also a poor indicator.

Children with high cholesterol are at the highest risk of having high cholesterol in their adult years. This may be prevented with regular exercise and by switching to low-fat, balanced diets with high protein content, such as the Mediterranean diet. Adults with high cholesterol can also add fish oil or Psyllium supplements to their diets, both of which may be of use in lowering cholesterol.