When most people think about the ketogenic diet, epilepsy doesn’t come to mind. But the “keto” diet has been used by doctors for more than a century to treat epilepsy in both children and adults. Created at the Mayo Clinic in 1921, the ketogenic diet was built on a tradition of fasting and other controlled diets used to treat epilepsy since at least 500 AD. At first widely prescribed, keto fell out of favor by mid-century as new epilepsy medications were developed. By the 1990s, many studies suggested it was an effective option for kids who weren’t helped by those medications. “Ever since then, it’s become popular as another treatment,” says Grace Shea, a registered dietician at Cincinnati Children’s Hospital who specializes in neurologic and ketogenic diets for kids.
If your child has epilepsy, you know how disabling seizures can be. Epilepsy medications can have challenging side effects, and about one in four kids have drug-resistant epilepsy (seizures that aren’t controlled by two or more drugs). That’s where the keto diet can come in. Studies suggest it can be as, or even more, effective than many anti-seizure drugs. “We consider the ketogenic diet another type of anti-seizure medication. It has pros and cons, just like medications have benefits and side effects,” says Alison May, M.D., an assistant professor of neurology at the Columbia University Medical Center’s division of child neurology.
What is the keto diet?
The ketogenic diet is a high-fat, very low-carbohydrate diet that includes just enough protein for growth and development. There are several versions of keto diets, but in the most common form, about 90 percent of daily calories come from fat.
On a standard diet, the body uses carbs as its main source of energy. Carbs are converted into glucose, which is stored in the liver. When you eat very low amounts of carbs on the keto diet, your body burns through your glucose stores. You then begin to burn fat for energy, which the liver converts into an alternate type of energy called ketones. The goal of the ketogenic diet is to put the body into ketosis, which is when the body relies mainly on ketones for energy. “We switch the way that you’re using energy,” says Shea.
Why does it work for seizures?
Scientists aren’t exactly sure why the keto diet helps to control seizures. “Some have thought that the ketones themselves have an anticonvulsant effect when they cross the blood-brain barrier,” Dr. May explains. While this is not yet proven, science has shown that increased ketones raise levels of the brain neurotransmitter GABA (a chemical messenger), though it is not understood if this happens directly or indirectly. These increased GABA levels are responsible for a decrease in the excitability of brain neurons, thereby stabilizing the brain, and warding off, or otherwise controlling seizures.
When is it used to treat children with epilepsy?
In most cases, your child’s doctor may suggest the ketogenic diet if your child has tried at least two seizure medications and is still having frequent seizures. “But the more that it’s being used, and the more we’re seeing the effects of it, people aren’t waiting as long to use it,” Shea says.
For children who qualify for epilepsy surgery, but are too young to undergo it, doctors may recommend a keto diet “as a bridge to surgery, and then a little bit after surgery you’d wean off keto like you would a medication,” Shea says.
Some conditions have been shown to consistently respond well to the ketogenic diet, says May, such as Dravet Syndrome, Doose Syndrome, GLUT1 Syndrome, Pyruvate Dehydrogenase Deficiency, and for those who have refractory infantile spasms, not to mention many others.
Before starting the keto diet, Shea says all kids should undergo tests to ensure it’s safe and appropriate. Some kids may have an unknown nutrient deficiency that can be treated before beginning keto, for example. On the other hand, some children may not be able to go on a keto diet because they struggle to gain weight or have severe feeding problems. The keto diet is off-limits if a child has a metabolic disorder that affects how their body uses long-chain fatty acids since fat is the backbone of the diet, says Shea.
How the Keto diet works
The main goal is to eat a very specific proportion of fat to carbohydrates and protein. You have to measure and weigh everything your child eats. The classic keto diet involves a 4:1 ratio of fat to carbs and protein. This means there are 4 grams of fat per every 1 gram of carbs and protein combined. Other types of modified keto diets have a 3:1, 2:1, or even 1:1 ratio.
“We typically start on a lower ratio, more like a 2:1. Then we monitor their ketones. There’s an optimal range that we want it in,” says Shea. “Depending on the ketone numbers and their response to seizures, we may have to increase the ratio, meaning we’re adding more fat and taking away carbs.” Due to the complexity and rigidity, some families may decide that the diet is too restrictive or difficult to maintain and isn’t the right fit for their family, she adds. However, babies and children on feeding tubes are often put on keto, says Shea, which is easier to maintain.
The modified Atkins diet as an alternative
With the modified Atkins diet, meals don’t have to be weighed and measured as accurately as they do with the strict ketogenic diet. “They just get their daily goals, and then they can use household measurements to portion things out. It’s still low-carbohydrate and induces ketosis, but it’s just not as strict,” says Shea.
Children who are doing the modified Atkins diet may be able to start the diet at home, as long as they get lab work done regularly and are carefully followed by their healthcare team.
Hospitalization is usually the first step
Most of the time, kids are hospitalized for several days when they first start the keto diet, says Dr. May.
Hospitalization allows for close monitoring of your child. For example, your child’s urine and/or blood are tested to ensure the right level of ketones is reached. Your child is also monitored to ensure they’re handling the diet well.
Hospitalization is also a built-in support team for you. The team teaches you everything you need to know to prepare meals and monitor your child. “It’s an extensive lifestyle change,” says Shea. “The families practice how to weigh and measure the food here in the hospital. And we teach them how to use the meal-planning program.” Infants receive a special ketogenic formula and can usually continue to breastfeed as well, if desired by both mom and baby. The team will prepare you for your return home, coaching you on maintaining the diet and testing urine at home, for example.
Maintaining the keto diet at home
Your child’s keto menu depends on your child’s age and weight, your dietary habits (whether you’re kosher, for example), and the ratio of fats to carbs and protein that the doctor prescribes. But generally speaking, you’ll need to focus on serving lots of high-fat foods, such as avocado, oils, butter, cheese, heavy cream, and mayonnaise.
The right protein sources are also important. “We really want to meet those protein needs, to help them grow,” says Shea. While animal products are a great protein source, keto is possible even if your family doesn’t eat meat. “You can certainly do this as a vegetarian. If the child is vegan, that’s a little bit harder, because it’s hard to get in all the protein, but it can be done,” says Shea.
The few carbs your child eats should come from specific fruits and vegetables, such as berries, broccoli, and greens. “No sweets, breads, pastas or anything like that,” says Shea. “We really try not to have carbs come from keto breads or crackers.” Your healthcare team will also point out other potential sources of carbs to avoid, such as certain toothpaste or mouth washes.
A registered dietician will recommend the right number of calories for your child—which varies a lot, says Shea. Since the ketogenic diet is so restrictive, your child will need to take supplements to ensure they’re getting all of the vitamins and minerals they need.
With time, your doctor may also reduce your child’s medication. “Many children are on the diet and medication at the same time,” says May. “Once an appropriate level of ketosis is achieved and tolerated, if seizures are controlled, a medication may be lowered.” In other cases, a medication might be added after a trial period of the diet. “We really look at their seizure response to help indicate that,” says Shea.
“It can be challenging, especially early on. It requires frequent checks of ketones, glucose, and other bloodwork as well as visits to the neurologist,” says May. “It’s a completely different way of eating. I give so much credit to these parents because they do an amazing job with this huge adjustment,” says Shea.
Unless your child doesn’t tolerate the keto diet, you’ll usually be encouraged to stick to it for at least three months to see if it’s working. “It can take the body a decent amount of time to get used to it,” says Shea. However, you may start to see benefits sooner. “We have had parents that say they can see changes within a couple of days,” says Shea. For others, it may take a couple of weeks or several months.
“Large studies in children on the diet have shown approximately 60 percent of children have a greater than 50 percent seizure reduction, and 30 percent have had a 90 percent reduction,” notes May. Some research has found that nearly half of kids can go off medication entirely. For some, seizures disappear entirely.
May says many of her patients’ parents mention improvements in responsiveness and development. Shea says some parents see behavior or cognitive changes, or increased energy. “It’s such a wide range of potential improvements,” she says.
If the diet has helped your child, it’s generally safe to gradually taper off after a couple of years.
In some cases, seizures may come back and the doctor will adjust your child’s medications—but not always. Some kids who have fewer or no seizures on keto may see those benefits last after they stop the diet, says Shea. “Some studies suggest there can be as high as 80 percent of children who remain seizure-free after a wean off the diet, if they had been seizure-free on the diet for two years or more,” says May.
Risks and downsides
As with any medication or treatment, there can be side effects. These include a higher risk of:
- kidney stones, due to uric acid buildup in the blood
- low electrolyte levels
- vitamin deficiencies
- constipation, due to decreased fiber-rich foods
- dehydration, due to the diet’s diuretic effect seen in some children
- weight changes
“This is not to say that all or any of these are going to happen,” says Shea. Furthermore, many side effects are manageable through diet or over-the-counter supplements or medications, she adds. Research also points out that there’s not enough evidence to understand the keto diet’s impact on children’s growth, cholesterol levels, and bone health in the long-term. “Close monitoring and follow-up with a ketogenic diet team helps reduce any of these side effects or long-term unknowns, to where children are growing and thriving while on such a specialized diet,” says Shea.
Bottom line: As effective, but difficult to maintain
The keto diet can be challenging to maintain once you leave the hospital, potentially preventing continuance. However, for many children seizures disappear entirely, making it worth consideration, especially for children with drug-resistant epilepsy. “It is a great option for specific seizure types,” says Dr. May. Parents also report developmental improvements, which is usually the case when seizures are controlled, regardless of the control method. The most important factor for success is working closely with your child’s neurologist and your ketogenic team. This is true if you decide to try a modified Atkins approach, as well. Your team will provide the support you need to maintain the diet while reducing any potential risks.
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