My First Encounter with the Ketogenic Diet for EpilepsyOver 20 years ago in the early 1990's, I was participating in a parenting group on the Internet when tragedy struck one of our members. J's infant daughter began to suffer from a disorder called "infantile spasms" (also called West syndrome) - a rare form of epilepsy. She was having dozens of seizures a day, and her demeanor changed from that of a smiling, engaged infant to an unhappy baby who avoided eye contact and cried a lot of time. The doctors told the family that their daughter would probably be extremely developmentally delayed, and might never walk or talk. They tried various medications, some of which helped for awhile, but the seizures always returned. In desperation, the parents were considering surgery to remove half of their daughter's brain.
Some months after the diagnosis of infantile spasms, J. read about a dietary treatment for epilepsy called a ketogenic diet. This was an old treatment for epilepsy which originated in the 1920's, but when effective medications were developed it had been more or less forgotten. Now, some doctors were experimenting with reviving it for children whose seizures weren't responding to medications. The mom convinced their neurologist to give it a try.
When I first heard her talk about the diet, I have to admit it sounded kind of crazy to me, as the diet was almost all fat (this was before I had heard much about low-carb diets). But hallelujah, it worked! Within a few weeks, the baby was seizure-free and over time, she began to develop normally, going to school with her peers and doing well. Her parents considered the ketogenic diet "a miracle".
Fast forward 20 years, and the ketogenic diet for epilepsy has been studied fairly extensively, and is now a standard back-up plan for children (and even some adults) whose epilepsy is difficult to control with medication. With over 300,000 children in the U.S. with seizure disorders, this has become an important addition to the arsenal of treatments for epilepsy.
It is vital that anyone using this diet for a seizure disorder do it under the supervision of an experienced physician and dietitian. There are many nuances and individual variations that will influence the exact diet for each person, and coordinating this with medications can be tricky. This is not something that should ever be attempted on your own.
What is the Ketogenic Diet for Epilepsy?(Note: I am using the term "Ketogenic Diet for Epilepsy" to distinguish it from the general term "ketogenic diet", as the version used for epilepsy is really one type of ketogenic diet. I will abbreviate it as KDE.)
The KDE is a very high-fat diet, with just enough protein for body maintenance and growth, and very low amounts of carbohydrate. In this state, the body generates molecules called ketones (also called ketone bodies) when fats are metabolized. Ketones are (largely) water-soluble, so are easily transported to the brain -- whereas the brain cannot use fatty acids for energy, it can use ketones for a large portion of its energy requirements. The goal of the KDE is for the brain to use ketones for energy rather than glucose as much as possible.
The KDE is usually begun in a hospital setting, and often begins with a one to two-day fasting period (though there may be a trend away from both of these requirements). After determining the proper amount of protein (depending on age, etc.), the diet is structured as a ratio of fat grams to protein+carb grams. It usually begins with a 4:1 ratio, and then can be fine-tuned from there. The diet is often calorie-limited and fluid-limited as well. Additionally, no packaged "low-carb foods" (shakes, bars, etc) are allowed for at least the first month.
Because a gram of fat has more than twice the calories of a gram of protein or carbohydrate, this equation means that at least 90% of the calories in the diet come from fat. Obviously this is a very strict diet, and it takes time to learn how to put together meals that fit the formula. All food must be weighed and recorded.
A Typical Day's MenuBelow is a shortened description of a menu appearing in the publication "The Ketogenic and Atkins Diets: Recipes for Seizure Control" (citation below). It's meant to give the idea of what children eat on the diet, not an exact prescription. Remember, all of these foods are carefully weighed and measured.
Breakfast - Eggs made with heavy cream and butter, bacon, small piece of fruit
Lunch - Tuna salad (made with mayo and heavy cream) on lettuce
Dinner: Cheeseburger made with extra fat, small salad, green beans
Snacks: -"Keto Custard" made from egg and heavy cream
- "Keto Yogurt" made by mixing sour cream, heavy cream, and a small amount of fruit
- "Peanut Butter Balls" - a mixture of peanut butter and butter
In recent years, some variations of this plan have been substituting coconut oil or MCT oil for some of the heavy cream and butter.
How Effective is the Ketogenic Diet for Epilepsy?Studies generally show that about a third of patients will have at least a 90% reduction in seizures, and another third will experience a 50-90% reduction. This is really remarkable, considering that these are generally those whose seizures are not well-controlled with medications. (Note that the term "epilepsy" encompasses a group of disorders with different causes that are not all fully understood, which is part of the reason different people respond to different treatments.)
Why Does the Diet Work?There are a few theories about how and why the diet works, but no one knows for sure. Changes in neurotransmitters, gene expression, and influences on neuron receptors are some of the possibilities.
How Long Are Children Usually on the Diet?Usually weaning off the diet is attempted after two years, though some children are kept on the diet for longer. In the story at the top of the page, J. successfully weaned her daughter after two years, and the seizures did not return.
Are There Alternatives to the Super-Strict Ketogenic Diet?Yes. A popular alternative that helps many is called the Modified Atkins Diet. This diet is far less restrictive, as calories, fluids, and protein are not measured. Generally, the diet begins with 10 grams of carbohydrate per day for the first month, and then slowly moving to 15 or 20 grams. It is similar to a very strict Induction phase of Atkins. There has been at least one study, though, where some achieved better seizure control when they switched from the Atkins diet to the KDE.
Can Adults with Seizures Benefit from the Ketogenic Diet?Yes. There have been a few studies of the modified Atkins Diet in adults with seizure disorders, and the results are fairly similar to studies with children. Interestingly, it was remarked in one of the reports that it was more difficult to keep adults on the diet, since they obviously have more control over what they eat.
Huffman, J, Kossoff EH State of the ketogenic diet in epilepsy. Current Neurology and Neuroscience Reports. 6:4 (2006) 332-40
Kossoff, et al. Will seizure control improve by switching from the modified Atkins diet to the traditional ketogenic diet? Epilepsia 51:12 (2010) 2496-2400
Levy RG, et al. Ketogenic diet and other dietary treatments for epilepsy. Cochrane Database of Systematic Reviews. 14:3 (2012)
Lutas, A and Yellen, G The ketogenic diet: metabolic influences on brain excitability and epilepsy. Trends in Neurosciences. 36:1 (2013) 32-40
Turner, Z et al The Ketogenic and Atkins Diets: Recipes for Seizure Control. Practical Gastroenterology. June (2006) 53-64.
Weber, S, et al. Modified Atkins diet for children and adolescents with medial intractable epilepsy. Seizure. 18:4 (2009) 237-240