What is a Ketogenic Diet?

Image for ketogenic diet article The body breaks down carbohydrates (carbs) into glucose. Glucose is used for energy. If there aren’t enough carbs, the body will break down fat sources instead. This process produces ketones for energy.

A ketogenic diet is a high-fat, low-carb diet. The goal is to make the body rely on more ketones than carbs for energy.

Why Follow a Ketogenic Diet?

A ketogenic diet has been linked to fewer seizures in people with epilepsy. It is not clear why the diet has this benefit. It is thought to be due to the shift from glucose to ketones. The classic diet for seizure control is made up of 3 to 4 parts fat and 1 part carb and protein.

Ketogenic Diet Basics

A ketogenic diet is based on high-fat foods. This includes butter, heavy whipping cream, mayonnaise, and oils. It also includes proteins, such as meat, fish, and poultry. The diet avoids carbs, such as sugar, bread, and pasta. Other carbs are very limited.

All food on this diet must be tracked. A certain ratio of fat to carb and protein is needed. All sources of carbs must be also be identified. This will include things like medicine and toothpaste.

It is hard for most people to stick to the diet because it is so strict. Many do not like the food choices and become bored with high-fat items.

This diet must be started under care of a doctor or medical team. It must also be watched closely by a dietitian. A person's blood sugar and ketone levels will need to be tracked. The diet does not have enough vitamins and minerals. Supplements may be needed to help a person get proper nutrition.

Eating Guide for a Ketogenic Diet

This guide is based on The Ketogenic Diet Resource plan. A doctor or dietitian will figure out how much fat, carbs, and protein should be eaten.

Food Category Daily Amount* Key Tips Key Nutrients
Grains Do not eat. Grains must not be eaten because they are high in carbs.  
Vegetables Eat 1 to 2 cups of salad greens and 1 cup of high fiber vegetables.
  • Salad greens include cabbage, chives, lettuce, spinach, kale, and chard.
  • High-fiber vegetables include sprouts, asparagus, bell peppers, broccoli, Brussels sprouts, celery, and cucumber.
  • Limit high-sugar vegetables, such as carrots, to ½ cup.
  • Vitamin K
  • Fiber
Fruits
  • Fruit is high in carbs and must be limited.
  • Avoid all fruits except ½ cup servings of berries.
Opt for strawberries, raspberries, blueberries, and avocado. Vitamin C
Dairy
  • Limit to 4 tablespoons of dairy cream a day.
  • Limit to 4 ounces of cheese per day.
  • Do not drink milk and half and half to avoid carbs.
  • Opt for heavy cream, whipping cream, or sour cream.
  • Avoid processed cheeses; choose Swiss, cheddar, Brie, goat, or mozzarella.
  • Calcium
  • Vitamin D
  • Protein
Legumes, Nuts, Eggs, and Other Protein-Rich Foods
  • Avoid legumes because they are high in carbs.
  • Limit nuts and nut flours to 1 ounce per day.
  • Eat plenty of meat, fish, and eggs.
  • Fish and shellfish, red meat, poultry, pork, bacon (grass-fed meats are best)
  • Peanut butter and macadamia nuts
  • Whole eggs
  • Protein
  • Omega 3 (supplements may also be needed)
Oils Saturated and monosaturated fats make up most of the daily intake. Opt for olive oil, avocado oil, or coconut oil instead of vegetable oils, such as corn and canola. Vitamin E
Fats and Sweets
  • Saturated and monosaturated fats should make up most of the daily intake.
  • Avoid sugar and artificial sweeteners.
  • Butter, beef tallow, chicken fat, avocado, tuna or fish, and shellfish
  • Avoid all sweets, such as cookies, candy, and desserts.
Omega 3 nutrients

*Based on a 2,000 calorie diet. This amount varies based on age, sex, and activity level. Individual amounts can be found at www.choosemyplate.gov.

Tips

  • Meet with a dietitian. They can help a person meet their nutrient needs. They can also help make meal plans.
  • Do not eat processed foods while on this diet. They may have hidden sources of carbs and offer little nutrition.
  • Drink plenty of unsweetened beverages. This includes almond milk, herbal tea, and water. It will help a person stay hydrated. It may also reduce constipation, a common issue with high-fat and protein diets.
RESOURCES:

The Charlie Foundation
https://www.charliefoundation.org

Epilepsy Foundation
https://www.epilepsy.com

CANADIAN RESOURCES:

Epilepsy Canada
https://www.epilepsy.ca

Health Canada
https://www.canada.ca

REFERENCES:

Classic keto. The Charlie Foundation website. Available at: https://www.charliefoundation.org/explore-ketogenic-diet/explore-2/classic-ketogenic. Accessed August 20, 2020.

Ketogenic diet. Epilepsy Foundation website. Available at: http://www.epilepsy.com/learn/treating-seizures-and-epilepsy/dietary-therapies/ketogenic-diet. Accessed August 20, 2020.

Ketogenic diet in adults. EBSCO DynaMed website. Available at:https://www.dynamed.com/management/ketogenic-diet-in-adults. Accessed August 20, 2020.

Ketogenic diet in children. EBSCO DynaMed website. Available at:https://www.dynamed.com/management/ketogenic-diet-in-children. Accessed August 20, 2020.

Last reviewed March 2020 by EBSCO Medical Review Board Dianne Scheinberg Rishikof MS, RD, LDN