The Typical Ketogenic DietThis diet is not easy to maintain, as it requires strict adherence to an unusual and limited range of foods. A typical ketogenic diet is usually made up of between 3 and 4 grams of fat for every 1 gram of protein and carbohydrate (a 3:1 or 4:1 ratio). This means that foods high in fat, such as butter, cream, and oils (canola or olive), make up the majority of a person's diet. Foods high in carbohydrates are limited. This includes breads, grains, and cereals. This diet also includes a partial restriction of fluids.
Because of the possibility for vitamin deficiencies, vitamin and mineral supplements are recommended for people following this diet, including vitamin D, calcium, iron, and folic acid.
There are several different variations of the ketogenic diet. Usually, the diet is started in the hospital under close supervision. For the first 24 hours, no food is given. The diet is then started by slowly increasing the calories.
Depending on which variation is recommended and how well seizures are controlled, the diet may be continued for two years. At that point, the healthcare provider may recommend slowly weaning the person off of the diet. Just like with epilepsy medications, if the diet is stopped suddenly, seizures may become much worse.
People on the ketogenic diet continue to take their medications, although it may be possible to reduce the amount based on how they respond.
What Does Research Say About This Diet?The ketogenic diet has not been widely studied. This may explain one reason why healthcare providers are hesitant to recommend it as a possible epilepsy treatment. However, several studies have shown the diet can help reduce or even eliminate seizures in people for whom they were not controlled on epilepsy medication.
One study of 150 children whose seizures were poorly controlled by medication found that about one-fourth of the children had a 90 percent or better decrease in seizures with the ketogenic diet, and another half of the group had a 50 percent or better decrease in their seizures. Other studies have shown that some children can stop the diet after several years and remain seizure-free.
Researchers are not sure how ketosis prevents seizures. One study showed that a byproduct of ketosis, called beta-hydroxybutyrate (BHB), inhibits seizures in animals. If BHB also works in humans, researchers may eventually be able to develop drugs that mimic the seizure-inhibiting effects of the ketogenic diet.