What Is the Ketogenic Diet?
Studies have shown that, in some cases, children with
epilepsy may experience fewer
seizures if they maintain a strict diet rich in fats and low in carbohydrates. Called the ketogenic diet, this causes the body to break down fats instead of carbohydrates for energy (a condition known as ketosis). With ketosis, the body creates high levels of ketones, which, besides providing energy for the body, may control
epilepsy symptoms (this is one of the theories behind why the diet works).
This diet is not without controversy. Healthcare providers are not exactly sure how the diet works, there have not been any large studies to verify how successful it really is, and a ketogenic diet can be difficult to maintain.
Who Does This Diet Benefit?
The ketogenic diet dates back to the early 1920s, before effective
epilepsy medications were available. However, because other treatments are now available, this plan is often only recommended in children with severe epilepsy symptoms that do not respond to several different
seizure medications.
One of the most common types of epilepsy
(see Epilepsy Types) for which this diet may be recommended is
Lennox-Gastaut syndrome. The ketogenic diet is not usually recommended for adults with epilepsy.
The Typical Ketogenic Diet
This 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.
Possible Side Effects of a Ketogenic Diet
This diet is not without side effects. Most side effects are minor, though, meaning that they can be treated without stopping the diet.
Possible side effects of the ketogenic diet include but are not limited to:
People who try this diet should seek the guidance of a dietitian to ensure that it does not lead to serious nutritional deficiency. It also is important to have close contact with healthcare providers, who can answer any questions or concerns about the diet or possible side effects.
