When the body burns (metabolizes) fat, it creates substances called
ketones. The ketogenic diet tries to force the body to
use more fat for energy instead of sugar (glucose) by increasing fat and
restricting carbohydrates. The ketogenic diet can be used to prevent seizures in an adult or a child who has any type of epilepsy. It is not yet clear how or why the ketogenic diet
prevents or reduces seizures.
One version of the ketogenic diet provides 4
grams of fat for every 1 gram of protein and carbohydrate together. People on a
ketogenic diet have to eat mostly fatty foods, such as butter, cream, and
peanut butter. Foods such as bread, pasta, fruits, and vegetables have to be
severely limited. And the person's total calories are also
restricted. At every meal, the food has to be measured carefully so that the
right amounts of each food are given. Even a slight departure from the diet can
cancel its effect.
The ketogenic diet is very strict and can be hard for some people and families to follow. Other special
diets for epilepsy that are less strict may also be tried.
What To Expect After Treatment
A person usually has to fast the day
and night before starting the diet. The diet is gradually introduced over
several days, so that the body can get used to the dramatic change. The person
may feel tired and lack energy during the first few days.
are usually admitted to a hospital or epilepsy center when they start the diet. There, the child can be watched and parents and caregivers can get training on how to do the diet at home. The ketogenic diet should always be given under the
supervision of a doctor and a dietitian.
When it works, the ketogenic diet works quickly to reduce seizures. People usually start having fewer seizures in 2 to 3 weeks. In 2 to 3 months you will be able to tell how well it is working.
Why It Is Done
The ketogenic and other diets may sometimes be
used to treat people who have severe seizures and who have not responded to
How Well It Works
In one study, children on the ketogenic diet had about one-fourth as many seizures as kids who weren't on the diet. So a child who wasn't on the diet had 4 seizures for every 1 seizure that a child on the diet had.1
Evidence shows that the ketogenic diet works about as well as medicines to control seizures in children.2
There is less evidence for special diets in adults with epilepsy, but a modified version of the Atkins diet may work as well as the ketogenic diet to control seizures.2
Special diets for epilepsy are not considered healthy, and they can have side effects. Some of the side effects make it hard to continue the diet. Side effects include:
Digestive problems, such as diarrhea, constipation, nausea, vomiting, and heartburn.
- High cholesterol (some people may need to take medicine).
- Kidney stones.
- Low energy levels.
- Slower growth rates in children.
- Vitamin and mineral deficiencies which can be helped by taking supplements.
Everyone on the diet needs close supervision by a doctor
and a dietitian.
What To Think About
If you are thinking about the ketogenic diet, keep in mind:
- For the diet to prevent seizures, your child
has to follow it exactly. The amounts and types of foods eaten have to be
measured precisely. And preparing meals can take a lot of time.
diet does not work for some children, no matter how closely they follow
The ketogenic diet is very strict and can be hard for some people and families to follow. Other special diets for epilepsy that are less strict may also be tried.
The medium chain triglyceride (MCT) diet. People on this diet take an oil supplement instead of relying on food for the fat in the diet. This can make the diet easier, because less total fat is needed from food and the person can eat more protein and carbohydrates.
The modified Atkins diet. The Atkins diet is known as a high-protein, low-carbohydrate diet. The modified Atkins diet for people with epilepsy is similar to the ketogenic diet but allows for a little more flexibility in protein, fluid, and calorie amounts.
The low glycemic index. This is the least restrictive special diet for epilepsy. It does not restrict fluids or protein and people do not need to be so strict about calories or the amount of fat they eat. People on this diet still eat much more fat than in a typical diet, but carbohydrates are not as limited.
Complete the special treatment information form (PDF)(What is a PDF document?) to help you understand this treatment.
Neal EG, et al. (2008). The ketogenic diet for the treatment of childhood epilepsy: A randomised controlled trial. Lancet Neurology, 7(796): 500–506.
Levy RG, et al. (2012). Ketogenic diet and other dietary treatments for epilepsy. Cochrane Database of Systematic Reviews (3).
Primary Medical Reviewer
||John Pope, MD - Pediatrics
Specialist Medical Reviewer
||Steven C. Schachter, MD - Neurology
Current as of
||March 12, 2014