Studies have shown that children with epilepsy can benefit from a special high-fat, low-carbohydrate diet, physicians of pediatric neurology at Chang Gung Memorial Hospital said.
Children who stayed on the food therapy — known as a ketogenic diet — for more than a year, 30 percent to 70 percent of them had their seizures reduced by more than 50 percent, and a further 10 percent to 20 percent became seizure free, the studies showed.
A ketogenic diet, which also contains adequate protein, was originally designed to mimic the physiological effects of “fasting” that was found to control seizures and which was practiced as a treatment before anticonvulsant drugs were introduced in the 1920s, said Hsieh Meng-yin (謝孟穎), a pediatrician who specializes in brain diseases at the hospital.
The hospital physicians warned however that the diet could be ineffective for certain patients and can be accompanied by unwanted side effects.
Hsieh said that according to studies, about 70 percent of the patients diagnosed with epilepsy can instead be treated by monotherapy, usually with a first or second round of antiepileptic drugs administered.
However some remain immune to the drugs from the outset, she said, adding that food therapy and surgery are two alternatives for this drug-resistant group, or for those whose seizures can no longer be controlled by drugs.
Yet the hospital’s epilepsy food therapy team said surgery is viable only if doctors know which part of the patient’s brain is causing the electrical storm, adding that compared with food therapy, it is a procedure that comes with higher risk, side effects and cost.
Ketogenic diet prescribes a certain ratio of fat to carbohydrate and protein. In one type of ketogenic diet, the ratio would be 4:1, with 90 percent of the energy from a meal sourced from fat.
A medium chain triglyceride (MCT) ketogenic diet — which Chang Gung Memorial Hospital has been offering as a treatment to those with intractable epilepsy — along with modified Atkins diet and low glycemic index treatment are other options to treat epilepsy.
They work either by increasing the percentage of carbs in the diet, or dispensing with the need to weigh foods and instead check fat ratios by measuring daily the levels of ketone — produced when fat is broken down by the body for energy — in urine.
The MCT ketogenic diet used at Chang Gung Memorial Hospital has resulted in nearly 50 percent of 53 people enrolled being able to reduce their seizure count more than 50 percent after three months.
“For those who continued to the 12th month, 85 percent of them experienced a more than 50 percent seizure reduction and 64 percent are seizure free,” Hsieh said.
“With reduced carbohydrates, glucose produced in the body for energy decreases as well. Instead, the liver converts the higher fat intake into fatty acids from which ketone bodies are produced. The ketone bodies replace glucose as the major fuel source for the brain,” she said.
“Some suspect that low carbohydrate intake, or reduced glucose metabolism, might be what is performing seizure control rather than the ketones, since there are also studies indicating that ketone levels do not correlate with the level of seizure control,” she added.
Wang Hui-hsiung (王煇雄), attending physician of pediatric neurology, added that recent studies have begun to probe the potential of a ketogenic diet as a viable treatment to diseases such as Parkinson’s, diabetes and malign cancers.