In the four-year study, the Johns Hopkins Children's Center team followed 121 epileptic children with intractable seizures on the high-fat, low-carbohydrate ketogenic diet designed to control such seizures. While most children developed high cholesterol after starting the diet, cholesterol gradually improved in nearly half of them, returning to normal or near-normal levels, with or without modifications to their diet to reduce fat intake.

Researchers prescribed dietary modifications to increase "good," polyunsaturated fats in the diets of 15 children with elevated cholesterol. Dietary modifications decreased cholesterol by 20 percent in 60 percent children whose diets were modified.

Surprisingly, cholesterol also dropped by at least 20 percent in 41 percent of the 37 children whose diets remained unchanged. The findings, while encouraging overall, also mean that relying on diet changes alone may not do much for those children in whom cholesterol remains persistently elevated, and that new approaches for these patients are needed, the researchers say.

The findings are reported in the Journal of Child Neurology.