The ketogenic diet
The ketogenic diet (KD) is high in fat and low in carbohydrates (carbs) and may be helpful in treating your child's seizures. The diet can be used for children with multiple different seizure types or epilepsy syndromes who have tried at least one to two antiepileptic drugs.
Normally, the brain uses glucose for energy. Most glucose is made from the digestion of carbohydrate-rich foods. But in the KD, the body is forced to burn fat for energy to produce ketone bodies, which are thought to have an anti-seizure effect in the brain. Ketones can be measured in the blood and urine.
To start the diet, the child usually needs to be hospitalized for a few days. Our team follows a protocol that allows the child to gradually adjust to the full strength diet. During hospitalization the team carefully monitors urine ketones, blood sugar levels, toleration of the diet and possible side effects. In the KD meal plan, fat is eaten in the form of heavy whipping cream, butter, mayonnaise and oil. Foods such as pasta, rice, cereal, milk and sweets are not included.
It is important that the child eats only the foods prescribed for the diet. Even a small amount of carbs can upset ketone production and therefore dramatically affect seizure control. Carbs found in medications, supplements, food and drinks are calculated into your child’s diet in precise proportion to the fat. The KD is expressed in terms of a ratio of grams of fat for each gram of protein plus carb in a meal (fat: protein + carb). For example, a 4:1 ratio means the diet has four grams of fat for each gram of protein plus carbohydrate. Ratios are determined by your dietitian and physician according to the individual needs of the child.
All meals need to be weighed on a gram scale prior to eating. It is important to eat all of the food at each meal to maintain the specific ratio prescribed. The KD ratio can be adjusted by the dietitian to achieve maximum seizure control.
The diet's success rate
The ketogenic diet has a fairly high success rate. At least 2/3 of children who start on it see a greater than 50% reduction in seizures. Of those children, at least 1/3 of them will see a 90% or greater reduction in seizures or become seizure free. The diet has been known to work immediately, but it can take a couple of months to see the maximum effects.
The first several weeks of the diet may involve fine-tuning to meet the child’s individual needs. Most patients are on the ketogenic diet for about two to three years. When it is necessary to end the diet, the ratio is slowly decreased, allowing more carbs to be eaten.
Diet alternatives for seizure management
The KD can be very restrictive and might be difficult to initiate and maintain for some families. A far less restrictive version called the modified Atkins diet now exists to help with seizure control. Foods on the modified Atkins diet are restricted in carbs, but not in protein or calories. You do not need to weigh foods on a gram scale, and the child does not need to be hospitalized to initiate this diet. It is an effective and well tolerated diet for the treatment of seizures. It is the best option for older children and teens. Your dietitian will provide you with a packet of information on how to initiate it.
Sometimes the structure and strict regimen of the ketone diet is more powerful than the modified Atkins diet to combat seizures. A family will have more freedom in choosing type and quantity of foods, but the effectiveness is different from child to child. Some children will start on a modified Atkins and then advance to the ketogenic diet to see if they get better seizure control with a more restrictive diet.
Beginning the diet
Your child is usually admitted to the hospital for three to five days. Although fasting may cause quicker ketosis (elevation of ketones in the bloodstream), it also may cause nausea and vomiting due to the metabolism shift of burning fat for energy so quickly.
Our team will not fast your child during diet initiation. Instead of fasting, our protocol of ramping up the diet allows the body time to adjust to the high fat. The first three meals are a 1:1 ketogenic ratio. Meals four, five and six are a 2:1 ratio. Meal seven is the first complete meal at a 3:1 ratio, which usually happens on the third day of the diet. The team will decide the goal ratio for your child. Your child will be closely monitored by the dietitian. Parents will spend several hours with the dietitian during the initiation phase of the diet.
The dietitian will determine all of the meals for your child and teach you what you need to know about the management of the diet for when you return home. Once your child is safely tolerating the full strength diet at the goal ratio, discharge will be considered.
There may be side effects
The KD team will closely monitor your child throughout the hospital stay. Side effects such as nausea and vomiting sometimes occur because of the diet's high-fat content; however, with careful monitoring and fine-tuning, these can be minimized. Furthermore, slowly increasing the fat over the course of three days can help prevent this from happening.
While adjusting to increased ketone levels, your child may also be lethargic during the first couple of days or weeks. It is important to observe and note your child's energy level before and after starting the diet. After your child has adjusted to the ketogenic diet, many parents note increased alertness and less drowsiness.
Constipation is the most common side effect of the diet. Drinking enough fluid and including high-fiber, low-carbohydrate vegetables into the diet can help relieve constipation. The dietitian can assist with specific suggestions for constipation. According to our protocol, there is no fluid restriction and children can drink to thirst throughout the day. Daily stool softeners are encouraged in children who develop constipation as a result of the diet.
Kidney stones are a less common side effect that can also be prevented by drinking adequate fluids each day. If kidney stones have been a concern for your child in the past, inform the KD team. Appropriate tests and medications may be prescribed.
Another common side effect is elevated blood lipids including cholesterol and triglycerides. If lipids are elevated, they usually return to normal levels after tapering off the diet. Blood levels will be checked at follow-up appointments. Additional supplements may be recommended by the KD team to reduce blood lipids, especially if it interferes with the management of the diet. It is rare that the diet would be weaned due to elevated blood lipid levels.
Make diet adjustments
The prescribed diet for your child will be calculated with the goal of maintaining normal growth and maintaining high levels of ketones. Weight changes are carefully monitored at follow-up appointments, and the diet will be adjusted by the dietitian to maintain adequate growth, both for height and appropriate weight gain.During the first few months, adjustments to the diet are common. The dietitian will be in contact with you every week for one month after hospital discharge or whenever you have a question or concern about child’s diet management.
Follow-up appointments are scheduled for one month after hospital discharge and every three months thereafter. At your child's follow-up appointments, growth, labs and overall tolerance to the diet will be assessed.
Is the ketogenic diet nutritionally complete?
No. The KD is deficient in many nutrients, including calcium and many B vitamins that are essential for proper functioning. In order to meet your child's nutritional needs while on the diet, vitamin supplements are necessary. At a minimum, a multivitamin and calcium supplement is required. Most of them can be purchased at your local grocery store or pharmacy. Your dietitian will recommend the correct amount of vitamins along with any other additional supplements that might be needed on an individual basis.
What do I need at home?
Ketone levels are measured with ketone sticks — small strips that are dipped into the urine. The presence of ketone bodies in the urine tells us that your child is in ketosis, meaning that the body switched to burning fat for energy. In the first few months on the diet, ketones should be checked twice daily. The higher the ketone level, the better the potential for seizure control. You can buy ketone strips over the counter at your local pharmacy usually near the diabetes section.
You will also need an electronic digital scale. Since everything that your child eats is weighed on a gram scale, you must buy a scale and bring it with you to the hospital to learn and practice how to use it. Different brands and sizes are available. You may talk to your dietitian for specifics on buying an electronic digital gram scale.
A useful tool for the KD is a small spatula, so that you can scrape every morsel of food from plates and bowls for your child to eat. You want to be sure that every bite is eaten to completion, since all meals are precisely calculated and weighed on a scale. Small plastic containers are also helpful in taking meals with you when traveling. Meals can be prepared and stored in the refrigerator for the future using small containers with tight fitting lids.
Keep school personnel informed
School personnel should not adapt the student's diet in any way without parental permission. The health care team will help you to educate the school faculty about your child's special diet.
Additional support
Our multidisciplinary approach to your child’s treatment will include support for getting through holidays, obtaining resources for teaching your family and friends and sending your child to school — all while successfully being on the ketogenic diet.
How to make an appointment
For an appointment, call the Children’s Memorial Epilepsy Center at 773.883.6159. It may be necessary for your child to be seen by one of our experienced epileptologists before starting the ketogenic diet or other diet therapy for the treatment of intractable seizures. We are also happy to see your child on a consultative basis if your child is already on the KD. Our office staff is ready to assist you with your questions.
More resources
Find on PubMed (a service of the U.S. National Library of Medicine) a list of studies of the ketogenic diet conducted by Children’s Memorial epilepsy specialists »
A typical ketogenic diet meal plan:
|
MEAL
|
DAY 1 |
DAY 2 |
| Breakfast |
Scrambled eggs, orange slices, butter, heavy whipping cream |
Sausage links, strawberries, butter, heavy whipping cream |
| Lunch |
"Pepperoni pizza rounds": pepperoni, tomato sauce, green peppers, mozzarella cheese, butter/oil, applesauce, heavy whipping cream |
Hot dog, watermelon, mayonnaise, keto ice cream, flavored water |
| Snack |
"Macadamia buttercrunch": Macadamia nuts, butter, diet caffeine-free soda |
Jello parfait with heavy whipping cream |
| Dinner |
Chicken breast, carrots, mayonnaise, chocolate keto ice cream |
"Spaghetti": Spaghetti squash, ground beef, parmesan cheese, butter, heavy whipping cream |
Note: Serving sizes are not given since each child requires a different amount of food that is calculated by the dietitian.