Classic Ketogenic Diet for Epilepsy & Seizures

Known as the original ketogenic diet for seizures invented over 100 years ago

Classic Ketogenic Diet Overview

People with drug-resistant epilepsy have been using the classic ketogenic diet for over 100 years as a seizure management option. Many have seen a reduction in seizure frequency and been able to decrease seizure medications while on the diet.

The classic medical ketogenic diet for seizures is a high-fat, adequate protein, and low-carbohydrate diet. It works by changing the body’s metabolism to mainly use fat as a source of energy rather than carbohydrates, which helps with seizure control. This strict diet requires careful measurements of foods and must be prescribed by a physician and monitored by a ketogenic dietitian.

The classic medical ketogenic diet uses the “ketogenic diet ratio" to determine what foods can be eaten. It is the ratio of fat to combined carbohydrates and protein in grams.

Tips for getting started

Ketogenic dietitian, Vanessa provides 5 simple tips to help you optimize your success on the classic ketogenic diet.

Classic Ketogenic Diet Frequently Asked Questions

Who is the classic medical ketogenic diet recommended for?

The classic ketogenic diet is primarily recommended for people suffering with various seizure types when seizures are not well-controlled with anti-epileptic drugs. It is also recommended for people with certain metabolic conditions, including glucose transporter-type 1 deficiency syndrome (Glut1) or pyruvate dehydrogenase deficiency (PDHD).

How effective is the keto diet for managing seizures?

Drug-resistant epilepsy in children can be managed with a medical ketogenic diet. Studies have shown that:₁

More than 50% of children had their seizures improve by 50%
About 1/3 of children had more than 90% seizure improvement
About 10% to 15% of children were seizure free

Compared to children, adults have similar success rates in controlling the frequency of seizures with a medical ketogenic diet. However, adults may have more difficulties following the classic form of the diet due to its strictness and potential lack of support at home. Many adults choose the modified Atkins®* diet since it is less strict and easier to follow.

Starting the classic medical ketogenic diet: What is it like?

Depending on the ketogenic diet center, the diet may be started over a period of days in the hospital. Typically, the diet is initiated slowly. At some centers, the diet can be started in an outpatient setting, but still requires frequent visits to the clinic for labs and follow up.

Starting and staying on the diet is a team effort that involves the entire family, support system and a ketogenic diet team. During initiation, close monitoring and comprehensive education about the diet is provided.

How are meal plans calculated?

All meal plans, snacks, and drinks for the classic ketogenic diet should be calculated by a ketogenic dietitian. The calculation method uses exchange lists, rounded nutritional values, and nutritional averages.

The meal plan on the classic ketogenic diet is individually calculated because everyone has different needs that must be considered. A complete assessment of each person’s nutritional needs and medical condition are factored into the individual meal plan:₂

The optimal number of calories per day using a thorough medical assessment and nutritional history (includes activity level, frame size, medical condition and recent weight gains or losses)
The goal or desired ketogenic ratio, typically ranges from 3:1 to 4:1
100% of fluid needs
The recommended dietary allowance for protein
Low carbohydrate supplements to meet vitamin and mineral needs (typically calcium, vitamin D and a complete multivitamin with minerals)

The classic medical ketogenic diet: Are there any side effects?

About 25% of children on the classic medical keto diet for seizures experience side effects. Most of the possible side effects can usually be managed without having to stop the diet._3,4

The possible side effects of the classic medical ketogenic diet can include:

Constipation, diarrhea, vomiting, or other gastrointestinal symptoms
Weight changes
Decreased growth
High cholesterol
Kidney stones
Acidosis
Fainting or lack of energy
Muscle cramps
Hunger
Menstrual cycle irregularities

How long do people stay on the diet?

The medical ketogenic diet should be tried for at least 3 months to give the diet enough time to work and determine if there is a reduction in seizure frequency. You will work with your healthcare team to determine if and when this will happen.

If the diet is working, a person can remain on the diet for years. Ongoing discussions about the risks and benefits of continuing the diet will be discussed with your healthcare team.

If the decision is made to discontinue the keto diet for seizures, your ketogenic dietitian will help you to slowly wean off the diet over a period of weeks or months, depending on the length of time you were on the diet. Seizures may worsen for a subset of those who discontinue the diet.₂

Foods Allowed on the Classic Medical Ketogenic Diet

The foods included on the classic ketogenic diet are calculated into a “ratio” of macronutrients. The ratio is the grams of fat to combined carbohydrates and protein in grams, and typically ranges from 3:1 to 4:1.

This means that approximately 90% of the calories eaten on the diet are from fat. Since fat provides more calories per gram than carbohydrates and protein, the portion sizes of foods in meals will look smaller on a classic ketogenic diet. The kinds of foods that provide fat for a ketogenic diet can include butter, bacon, avocados, heavy whipping cream, mayonnaise, and oils (like canola or olive oil).

The classic ketogenic diet can indeed be another management option when anti-seizure drugs don’t work, but it can be complicated to follow. It is very important to prepare meals carefully, or the diet won’t help with seizure reduction. That’s one of the reasons why it is medically prescribed by a physician and supervised by a ketogenic dietitian.

Keto-Friendly Recipes

KetoCal can be used in recipes to help provide a consistent ratio & complete nutrition for peace of mind.

Discover Quick & Easy Recipes

Coco’s Story

……Coco was having hundreds of seizures a day…..We slowly started noticing a decrease in seizures and after six months of being on the [ketogenic] diet, we had seizure control…. The ketogenic diet has given Coco a better quality of life

References: 1. Devi, N., et al. (2023). Efficacy and Safety of Dietary Therapies for Childhood Drug-Resistant Epilepsy: A Systematic Review and Network Meta-analysis. JAMA pediatrics, 177(3), 258–266. 2. Kossoff EH, Zahava Turner RD, Cervenka MC, Barron BJ. Ketogenic Diet Therapies for Epilepsy and Other Conditions. 7th ed., Demos Health/Springer Publishing Company, 2021. 3. Newmaster K, et al. (2022). A Review of the Multi-Systemic Complications of a Ketogenic Diet in Children and Infants with Epilepsy. Children (Basel). 10;9(9):1372. 4. Kossoff, E. H., et al. Practice Committee of the Child Neurology Society (2018). Optimal clinical management of children receiving dietary therapies for epilepsy: Updated recommendations of the International Ketogenic Diet Study Group. Epilepsia open, 3(2), 175–192.

The content in this section is for informational or educational purposes only and does not substitute professional medical advice or consultations with your healthcare professional.