Aug. 19, 2003 -- Children with epilepsy who follow the ketogenic diet -- a rigidly high-fat, low-carbohydrate diet to control severe seizures -- experience dramatic and rapid increases in their cholesterol, researchers from Baltimore's Johns Hopkins Children's Center report.
Lead researcher Peter O. Kwiterovich Jr., MD, says the findings may have as much relevance for healthy children who eat diets that are very high in fat as adults who have adopted the high-fat, low-carb approach to eating as a lifestyle.
The Real Message
"The message is not that children with [uncontrollable] seizures should not be on this diet, because it can be remarkably effective and most children only stay on it for a few years," Kwiterovich tells WebMD. "But our findings suggest the distinct possibility that anyone who eats a very high-fat diet may be setting themselves up for later [blood vessel] disease."
The researchers followed a group of children with epilepsy who had been placed on a ketogenic diet after medications failed to control their seizures. Their study is published in the Aug. 20 issue of The Journal of the American Medical Association.
How the Ketogenic Diet Works
The strictly controlled, very high-fat diet, which is also low in carbohydrates and proteins, has been shown to reduce seizures dramatically or eliminate them completely in a significant percentage of children who are placed on it.
Eliminating all sugars and simple carbohydrates and severely restricting other carbohydrates results in a condition called ketosis, in which the body burns stored fat instead of glucose for fuel. It is not clear why ketosis inhibits seizures, but in an earlier Johns Hopkins study involving 150 children with difficult-to-control epilepsy, more than half had a 50% or greater reduction in seizures and one-fourth experienced a 90% improvement.
In the latest study, researchers measured cholesterol and triglyceride levels among 141 children accepted into the Johns Hopkins ketogenic diet program. The average age of the children was 4, and all had frequent epileptic seizures that could not be controlled with medication.
After six months on the diet, the children's average total cholesterol level skyrocketed to 232 -- well above normal. Overall, more than 60% of them had high total cholesterol.
When the children were followed for 12 to 24 months on the ketogenic diet, average total and LDL cholesterol levels decreased slightly but still remained high. At the 24-month cutoff, triglyceride levels were not significantly different than before the ketogenic diet was started.
Weighing the Risks and Benefits
Epilepsy specialist Gregory L. Barkley, MD, says the findings confirm what has been suspected for some time but they are unlikely to change clinical practice.
"This is something that physicians will want to include in their discussion about the risks and benefits of this particular treatment," the director of Detroit's Henry Ford Comprehensive Epilepsy Program tells WebMD. "But we know that uncontrolled seizures carry all kinds of risks. This remains a useful treatment. But like many treatments, it is not without risks."
What Does This Mean for Atkins?
The Atkins diet and other wildly popular low-carbohydrate eating plans represent somewhat less restrictive versions of the ketogenic diet. Recent studies have found that people who are losing weight on these diets typically see reductions in cholesterol and lipid levels.
But Kwiterovich says his results suggest that following these diets long term, in the absence of weight loss, may be dangerous.
"It is very possible that staying on an Atkin's-type diet for maintenance once weight stabilizes will cause an increase in cholesterol ... even though the same diet can lead to reductions while weight loss is going on," he says.