Why doctors may recommend the ketogenic diet for seizures

I recently heard from an LMNT customer whose 18-year-old son had just been diagnosed with epilepsy. The young man was seeking a sustainable treatment option that was not entirely dependent on pharmaceuticals or surgery. After doing some research, he decided to experiment with a ketogenic diet.

The evidence on carb restriction for seizure control stretches back to the days of the Ford Model T. To be clear, the keto diet isn’t a perfect, universal epilepsy therapy. It works for some people, but others will achieve better results with antiseizure medications or surgery.

In addition to low-carb diets, MCT (medium-chain triglyceride) oil appears to have antiseizure effects unrelated to its ketogenic properties. Adding MCTs to an existing low-carb regimen is kind of like adding sauna sessions to your exercise routine. You get a broader spectrum of benefits.

I wrote this article to be your practical guide on the ketogenic diet for seizures. I’ll cover the history of keto for epilepsy, potential mechanisms at play, which epilepsies keto can improve, three ketogenic diets to choose from, and how to get started.

The History of Keto for Epilepsy

Let’s take a little trip back to the 1920s. About a century ago, Harvard researchers noticed a remarkable phenomenon: two to three days of fasting significantly reduced seizure frequency in patients with epilepsy. During a fast, the body burns fat to produce molecules called ketones, an alternate energy source—and after two to three days of fasting, ketone levels typically begin to rise.

Dr. Russell Wilder of the Mayo Clinic took note of this and subsequently designed a diet to boost ketone levels without fasting. This “ketogenic diet” was super low in carbs, super high in fat, and pretty low in protein. Like fasting, this regimen kept insulin low and spurred the body into fat-burning, ketone-making mode.

And it worked! Not only did Dr. Wilder’s ketogenic diet produce similar results in patients with epilepsy, but patients could sustain it for significantly longer than fasting because they could continue to eat. But while his traditional ketogenic diet beat prolonged fasting, it was still a bear. This wasn’t the keto you may know today—it was a strict clinical regimen that essentially required patients to mainline butter, oil, and heavy cream.

The Charlie Foundation—founded in 1994 after 11-month old Charlie Abrahams utilized the ketogenic diet to halt a stubborn case of epilepsy—helped rekindle keto’s place in epilepsy treatment after it had all but been lost to the ages. But it wasn’t until 2003 that researchers tried applying a modified Atkins diet (which allows more protein and carbs) to a seven-year-old patient with epilepsy. It was originally intended as a transition diet, but her seizures vanished, so they stuck with it. She was seizure free for three whole years! Since then, more research has validated the modified Atkins diet as effective seizure therapy.

Why Does the Ketogenic Diet Reduce Seizures?

Multiple studies show that a ketogenic diet decreases the quantity and frequency of seizures in folks with epilepsy. So we know it works, at least for a big chunk of the target population. The question is why? We have clues, but there’s no clear cut answer.

One hypothesis is that ketones including beta-hydroxybutyrate, acetoacetate, and acetone have anticonvulsant effects. In some studies, injecting mice with ketones stops seizures. Other animal studies, however, haven’t found ketone levels to correlate with seizure reduction.

Another hypothesis involves the balance of the neurotransmitters GABA and glutamate in the brain. A ketogenic diet, it’s been shown, decreases the excitatory (pro-seizure) glutamate and increases the relaxative (antiseizure) GABA. Scientists believe this neural shift is mediated by a keto-induced bacterial shift in the gut. Thanks, gut bugs!

Eating a low-carb diet also minimizes blood glucose, potentially decreasing a seizure’s fuel supply. With less glucose (and more ketones) fueling the brain, the likelihood of seizures may decrease.

These general mechanisms are interesting, but we shouldn’t overlook more specific factors. For instance, which epilepsies in particular are improved by low-carb dieting?

Seizure Disorders Improved by Keto

Epilepsy isn’t just one condition. It’s a group of related disorders that can cause not only seizures, but also a loss of awareness and behavioral disruptions. A person is diagnosed with refractory epilepsy—aka intractable epilepsy—when two separate anticonvulsant drugs fail to reliably reduce seizures. The ketogenic diet shows promise for treating this stubborn condition, especially for those who are not candidates for surgery.

It also shows promise for treating other varieties of epilepsy. In 2018, a group of experts (the International Ketogenic Diet Study Group) convened to assess the impact of keto dieting on childhood epilepsy. They found keto to be beneficial (greater than 50% seizure reduction) for many seizure-related conditions, a sample of which I list here:

• Angelman syndrome
• Dravet syndrome
• Infantile spasms
• Pyruvate dehydrogenase deficiency (PDHD)
• Doose syndrome (epilepsy with myoclonic–atonic seizures)
• Super-refractory status epilepticus
• Tuberous sclerosis complex
• Complex 1 mitochondrial disorders
• Glucose transporter protein 1 (Glut-1) deficiency syndrome
• Febrile infection-related epilepsy syndrome (FIRES)
• Ohtahara syndrome

While keto seems to benefit folks with these conditions, it won’t work for everyone. As always, consult a medical professional before deciding on epilepsy therapies for you or a loved one.

3 Different Ketogenic Diets for Seizures

Here I’ll review three types of keto diet studied for seizure reduction. I’ll save the best for last.

#1: MCT-supplemented Keto

Medium-chain triglycerides (MCTs) are the most ketogenic form of fat. They also contain a compound (capric acid) with anticonvulsant properties. We shouldn’t be surprised, then, that the MCT-based keto diet can work for seizure control.

However, there’s a couple of problems with MCT diets. First, a tablespoon of MCTs can cause diarrhea. Now imagine getting most of your energy from this source. Second, an MCT diet isn’t very sustainable since nutritious whole foods are not high in MCTs.

#2: Traditional Keto Diet

This is the OG keto diet developed to treat epilepsy, and it’s about as flexible as a steel rod. Traditional, “classic” keto entails eating a 4:1 ratio of fat to protein plus carbs. For every 4 grams of fat, you’re allowed 1 gram of protein or carbs. That translates to roughly 90% of your calories coming from fat. Not only is classic keto hard to maintain, but its low protein requirements can be hard on your body. To optimize for overall health, I’d try this next approach.

#3: Modified Atkins Diet 

In terms of calories, the composition of a modified Atkins diet (MAD) is 50-65% fat, 25-35% protein, and <10% carbohydrates. An important note: this is not proportional to food mass, as fat contains 9 calories per gram versus protein and carbs’ mere 4 calories per gram.

These macro ratios won’t generate quite as many ketones as classic keto, but that may not matter for seizure control. In a 2019 meta-analysis, meaning an analysis of multiple scientific studies addressing the same question, researchers found that traditional and modified keto approaches have roughly the same efficacy.

Furthermore, there’s a case to be made for supplementing a modified Atkins diet with MCTs, starting at 1 tsp/day and then increasing slowly. We don’t have efficacy stats on this protocol, but a feasibility study suggests it’s well tolerated in women with epilepsy. Just go slowly when adding MCT’s to one’s diet. “Disaster pants” and epic gut cramps await the overly zealous.

Amidst all of this, please remember that some folks may not respond to keto. Medication or surgery may be necessary. I wrote another article for the full rundown on epilepsy treatment options.

Risks and Concerns

I’m a fan of low-carb diets that are high in protein, but I worry about long-term consumption of a classic ketogenic diet. It’s too low in protein to support muscle maintenance or (for children) proper growth and development. Since modified Atkins appears to reduce seizures, I suggest starting with that protocol, perhaps in conjunction with supplemental MCTs.

Two common side effects of keto (even modified keto) are weight loss and elevated LDL cholesterol. You can mitigate weight fluctuations by bumping up your caloric intake. Regarding cholesterol, ditch saturated fat for monounsaturated sources and eat plenty of non-starchy veggies for fiber. Fiber binds to cholesterol in the gut and helps carry it out through stool. Eating veggies may also improve many GI side effects of keto including constipation, gas, and diarrhea.

Also of note, a ketogenic diet increases the loss of fluids, sodium, and potassium through urine. Replace them with LMNT or your own homemade electrolyte drink to avoid the headaches, fatigue, cramps, and lethargy that come with dehydration and electrolyte deficiency.

A medical professional should monitor you (or your child) for hypoglycemia, acidosis, and muscle loss, especially if you’re tinkering with a classic keto diet.

Experimenting With a Ketogenic Diet for Seizures

I believe that a modified Atkins diet, perhaps with the addition of MCTs, is a reasonable protocol to try for seizure reduction. Plausible mechanisms (ketone production, GABA boosting, glucose lowering, etc.) plus clinical data support carb restriction for epilepsy. If modified Atkins doesn’t work for you, consider experimenting with a classic keto diet.

All the while, work with your medical professional to explore medications that may help. That’s what I told the parent I spoke with at the start of this article—treatment will vary with individuals. If keto works, that’s fantastic. But if it doesn’t, there are other options available.