Ketogenic Diet

What the Diet Does

Normally, our bodies run on energy from glucose, which we get from food. We can’t store large amounts of glucose, however. We only have about a 24-hour supply. When a child has no food for 24 hours — which is the way the diet begins, usually in a hospital — he or she uses up all the stored glucose. With no more glucose to provide energy, the child’s body begins to burn stored fat.

The ketogenic diet keeps this process going. It forces the child’s body to burn fat round the clock by keeping calories low and making fat products the primary food that the child is getting. In fact, the diet gets most (80 percent) of its calories from fat. The rest comes from carbohydrates and protein. Each meal has about four times as much fat as protein or carbohydrate. The amounts of food and liquid at each meal have to be carefully worked out and weighed for each person.

Doctors don’t know precisely why a diet that mimics starvation by burning fat for energy should prevent seizures, although this is being studied. Nor do they know why the same diet works for some children and not for others.

Trying to put a child on the diet without medical guidance puts a child at risk of serious consequences. Every step of the ketogenic diet process must be managed by an experienced treatment team, usually based at a specialized medical center.

Chances of Success

Often, a period of fine-tuning is needed before it’s clear whether or not a child is going to respond to the ketogenic diet. Doctors often ask parents to try the diet for at least one month, and even as long as two or three, if it’s not working at first.

A child on the diet usually continues taking anti-seizure medicine, but may be able to take less of it later on. If a child does very well, the doctor may slowly taper the medication with the goal of discontinuing it altogether.

About a third of children who try the ketogenic diet become seizure free, or almost seizure free. Another third improve but still have some seizures. The rest either do not respond at all or find it too hard to continue with the diet, either because of side effects or because they can’t tolerate the food.

A side benefit of the diet is that many parents say their children are more alert and make more progress when on the diet, even if seizures continue. If the diet seems to be helping, doctors will usually prescribe it for about two years. Then, they may suggest that parents slowly begin including regular food in the child’s diet to see if the seizures can still be controlled, even with a normal diet.

Sometimes a small amount of seizure medication is started again after the diet is stopped. However, some children may be able to stay seizure free without any further treatment. If the seizures return, the doctors may recommend putting the child back on the diet.

Side Effects

Like all the other treatments for epilepsy, the ketogenic diet has some side effects, which may or may not affect a particular child. Some side effects may go away if caught and managed early on. Knowing what to look for can make a big difference. Reported side effects include dehydration, constipation, and, sometimes, complications from kidney stones or gall stones.

Adult women on the diet may have menstrual irregularities. Pancreatitis (inflammation of the pancreas), decreased bone density and certain eye problems have also been reported. Again, this is why the medical team closely follows children or adults who are on the diet.

The diet lacks several important vitamins which have to be added through supplements. Sometimes high levels of fat build up in the blood, especially if a child has an inborn defect in his ability to process fat. This possibility can lead to serious effects, which is another reason for careful monitoring.

Making the Decision

Most experts say the diet is worth trying when two or more medications have failed to control seizures, or when medications cause side effects that are having a harmful effect on a child’s life. It also helps to have a child who is willing to try foods that he might otherwise not be enthusiastic about, and is tolerant and not fussy about eating.

The diet seems to work for more than one kind of seizure, and for children who have a lot of seizures or few seizures. But most doctors say it shouldn’t be used instead of medications if the drugs are working and the child is not having bad side effects. Parents generally decide to try the diet because they hope it will give their child a better chance for a normal life.

However, the diet can be a barrier to some normal life experiences for children, especially those that revolve around food and holidays. And, like other treatments for epilepsy, it also can have side effects that affect some children more than others. So, as with any kind of treatment, there’s a lot to think about before deciding to try the diet.

Going over all the possibilities with your doctor is the best way to make the decision. It may also be helpful to talk with other parents whose children have been on the diet.

More About the Ketogenic Diet:

Getting Started

The diet starts in the hospital.

The child is placed on a 24-hour fast and is closely watched to be sure he or she is handling the very real stress of not getting any food during that time.

Once the child begins burning fat for energy instead of glucose (a state called ketosis), the doctors gradually introduce the foods that are part of the diet in amounts that are right for that child.

When the child goes home, the parents continue to carry out the diet at home, weighing every item and making sure that the balance between fat and other nutritional elements is maintained. Doctors and dietitians follow children closely to make sure they’re getting enough nutrition and are growing.

Parents of children on the diet use special paper strips to check the ketone level in the child’s urine.

Ketones are the chemicals that the body produces when it burns fat. Parents also test urine weekly for blood, which could be an early sign of kidney stones, a possible side effect of the diet.

Working with a Dietitian

When children (or adults) are treated with the ketogenic diet, the dietitian is a very important member of the medical treatment team.

The dietitian works out how much of one type of food or another should be served together to make the diet work. He or she helps the family plan the child’s meals, and works out how many calories the child needs for healthy growth.

Meal plans serve small amounts of fruits or vegetables (carbohydrates) and meat, fish or chicken (protein) with lots and lots of fat (such as cream, butter, eggs, or mayonnaise), and no sugar.

The following sample meal plans provide a general idea of the kinds of foods that are part of the diet.


  • Scrambled eggs with butter
  • Diluted cream
  • Orange juice


  • Spaghetti squash with butter and Parmesan cheese
  • Lettuce leaf with mayonnaise
  • Orange diet soda mixed with whipped cream


  • Hot dog slices with sugar-free catsup
  • Asparagus with butter
  • Chopped lettuce with mayonnaise
  • Sugar free vanilla cream Popsicle

These examples don’t show the exact amounts of each food because those have to be worked out for each child by the dietitian.

Each portion of food must be prepared very carefully by the parents, who often use a gram scale to weigh items exactly.

That’s because a tiny mistake in weighing and measuring foods (or if a child finds and eats a few cookie crumbs, or puts anything containing sugar — including medicines and toothpaste — in her mouth), can break the diet’s effects — and cause a seizure.

Frequently Asked Questions

Will my child gain weight from eating so much fat?

On this diet, the amount of food is carefully weighed so that your child will eat all the calories she needs for good health, but not so many that she gains weight. The fat content of the food doesn’t affect weight if you strictly limit total calories.

How long should I sit with my toddler before I give up trying to get him to finish all his food?

Some parents report that mealtimes on the diet can wrap up in twenty minutes, while others say they have to sit with their children for two hours before all the food is finished.

A child must finish all the food because the meal is put together in amounts that will give him the right balance between fat, protein, and carbohydrates. If it’s not all eaten, the balance is lost, and the child may have a seizure.

Since this is important, parents often try tricks like playing a video during meals or playing games to distract the child while they’re encouraging the child to eat.

Parents who’ve been successful advise others to use the diet creatively, and try to offer something new and special for each meal to keep the child’s interest. Older children, who know that the diet is helping to keep their seizures away, may be more cooperative.

What about special holidays like birthdays and Thanksgiving?

The dietitian will be able to give you special recipes to keep the mood festive while allowing children to stick to the diet. If your doctor or dietitian is treating other children on the ketogenic diet, those parents may have good ideas to share with you. However, always check with your child’s dietitian before trying something new.

One family offers the following suggestion for Halloween, which is all about candy and sugary treats. They let their keto kid go trick or treating like the other neighborhood children, but when the child gets home, the parents buy back the candy and the child then uses the money to buy a special toy.

Will taking prescription or other medicines affect the diet?

All medicines and pharmaceuticals, from toothpaste to cough syrup to vitamins to prescription medicine, must, whenever possible, be free of sugar and other carbohydrates. Remind your doctor to prescribe all needed medications in sugar-free and carbohydrate-free forms. Read labels carefully and check with your pharmacist.

Does the diet cause a problem with high cholesterol?

When children are switched from a normal diet to a 90 percent fat diet, both cholesterol and triglyceride levels can go up. However, the ketogenic diet is not a lifetime diet. Children stay on it about two years. When weaned off the diet, most children return to their pre-diet levels.

What can my child eat at school?

Your dietitian will help you plan meals that can go to school with your child. Tuna, egg, or chicken salads are easy to carry in small plastic containers. Warm or chilled food can be carried in a small cooler or insulated bag, or wrapped in foil.

There are many celebrations at school that involve food. It’s very important for all the teachers and aides to know that your child cannot have the same treats that the other children get. You may want to ask school personnel to let you know in advance when treats are planned so that you can send a keto-correct treat for your child.

It’s a good idea to have a meeting with your child’s teachers and everyone your child comes in contact with at the beginning of every school year. Make them understand that even half a cookie or a bite of cupcake can lead to seizures, hospital, and the loss of seizure control.

Post a notice at school: This child must not be fed anything not brought from home.

How does my child explain the diet to his friends?

Young children say, “I’m a special kid on a special diet.” Older children can impress their friends by telling them about all the shakes, cheesecakes, pancakes and omelets they get to eat on their special diet.