While neurologists have known that a high-fat and very low-carb diet, known as a ketogenic diet, reduces seizures in epileptic patients who are resistant to medical therapy, the "why" to it all has always been a mystery.
But today, some scientists say they may have found the answer. Researchers at Dana-Farber Cancer Institute and Harvard Medical School said seizures might be linked to a protein that changes metabolism in the brain, which is why patients respond so well to the ketogenic diet.
Epilepsy is a brain disorder in which a person has repeated seizures, or convulsions, over time. The seizures represent episodes of disturbed brain activity and cause changes in attention and behavior, according to the National Institutes of Health. The condition affects about 3 million Americans and 50 million people worldwide, according to the Epilepsy Foundation.
The ketogenic diet mimics aspects of starvation by forcing the body to burn fats instead of carbohydrates. The diet produces ketones in the body, organic compounds that form when the body uses fat, instead of glucose, as a source of energy. An elevated level of ketone bodies in the blood reduces the frequency of epileptic seizures.
The study, published in the journal Neuron and conducted in genetically-altered mice, found that the effect of the ketogenic diet on epilepsy can be mimicked using a much more specific and non-dietary approach by manipulating a particular protein in mice, said Gary Yellen, a professor of neurobiology at Harvard Medical School and co-author of the study.
"This points toward potential new ways of treating epilepsy in patients for whom current drugs are not effective," said Yellen.
Yellen said that while the connection between epilepsy and diet has remained unclear for nearly 100 years, he has seen children's lives change drastically after changes in their food intake. In the past, some patients have also seen improvement when they cut nearly all sugar from their diets.
Experimenting in mice, the researchers found they could mimic the effects of the diet by altering a specific protein, known as BAD. Seizures decreased in the mice.
While the research must first be replicated in humans, Yellen said, in the long run, scientists should be able to target this pathway pharmacologically.
"Because the ketogenic diet can be so broadly effective against many types of epilepsy that are not well-treated by existing medications, tapping into its mechanism may be valuable for treating many epilepsy patients," he said.