The ketogenic diet and epilepsy

In recent years, the ketogenic diet, or "keto," has risen in popularity as a weight loss method. However, this widespread version of the diet is very different from the medical diet that has long been used as a treatment for epilepsy.

The ketogenic diet was developed nearly 100 years ago when researchers observed that fasting offers antiseizure benefits. In fact, the concept of fasting to treat seizures has deep historical roots and was even mentioned by Hippocrates, says Rana Said, M.D., a neurologist and epileptologist at Children's Health℠ and Professor of Pediatrics and Neurology at UT Southwestern.

"The ketogenic diet is a well-documented standard of care and a validated treatment for epilepsy," says Dr. Said, who started the Children's Health Ketogenic Diet Program in 2005. "We've used the diet safely and effectively in children with refractory epilepsy for years."

What is the ketogenic diet?

The ketogenic diet was created to simulate the metabolic effects of fasting, which forces the body to use stored fat as fuel. The ketogenic diet is low in carbohydrates, high in fat and has adequate protein for growth; about 90% of calories are fat-based. When carbohydrate intake is drastically reduced, the body does not have enough carbohydrates to use for energy. Instead, the body enters a metabolic state called ketosis, in which it burns fat for energy. Fat is broken down to fatty acids, which undergo a metabolic process that produces a substance called ketones in the body.

When referring to the ketogenic diet as a treatment for epilepsy, it is important that the diet is closely regulated and monitored by a physician, typically an epileptologist, and a dietitian.

"The ketogenic diet used in epilepsy treatment is one that is rigidly calculated and medically supervised," explains Dr. Said. "The diet is individualized based on each child's caloric and metabolic needs."

How does the ketogenic diet help with epilepsy?

The ketogenic diet has been proven to reduce seizures in some children with epilepsy. "Of the children in our ketogenic diet program, about a third who are not successful with medication will find a 75% reduction in seizures. Another third will experience a 50% reduction in seizures. The remaining third may have no significant improvement," says Dr. Said.

The ketogenic diet is one dietary therapy used to treat epilepsy. Other diets that may offer antiseizure benefits include:

• Modified Atkins diet (MAD)
• Low Glycemic Index therapy (LGIT)

Who can use the ketogenic diet as a medical treatment?

The ketogenetic diet is typically used as a treatment for children with refractory epilepsy, or children who continue to have seizures despite appropriate trials of antiseizure medications at adequate doses. The ketogenic diet is also used as a first-line treatment for children with certain metabolic conditions, even in the absence of seizures.

Before beginning the ketogenic diet, it must be discussed with your child's neurologist. The main goal of using the ketogenic diet for refractory epilepsy is to control seizures. This may or may not result in the reduction of other seizure medications.

Because of the neuroprotective effects of the ketogenic diet, research is now looking at its medical applications beyond epilepsy. Studies are currently looking at the effects of the ketogenic diet on autism spectrum disorder, diabetes, Parkinson's disease, Alzheimer's disease and even for use in brain tumors.

Are there any side effects of a ketogenic diet?

While some people may consider the ketogenic diet a "natural" treatment for epilepsy, Dr. Said explains that the diet itself is not a natural form of eating. "The ketogenic diet is not necessarily a healthy diet, unless you need it for the conditions in which we administer it," says Dr. Said.

Children on a ketogenic diet can experience side effects such as:

• Constipation
• Ketoacidosis
• Decreased appetite
• Kidney stones
• Nutrient deficiencies
• Weight loss

Because the ketogenic diet is high in fat, a child's lipid levels are monitored along with any subsequent conditions that may arise. The diet is deficient in key minerals and vitamins, so those need to be supplemented to provide proper nutrition.

To follow the diet properly, it's essential to understand both what a child can and cannot eat to avoid side effects. Strict adherence of the diet is required and even the smallest amount of deviation can reduce its benefits. "That's why an epileptologist and a nutritionist must be involved in the process and carefully monitor a child on the ketogenic diet," says Dr. Said.

How to support your child on a ketogenic diet for epilepsy

It's important that parents work with their child's neurologist before starting a ketogenic diet. This will:

• Help you understand your child's nutritional needs
• Increase your understanding of the diet and learn specifics about food options
• Provide resources and support throughout the therapy

The ketogenic diet can be challenging because many foods and products have hidden carbs. "For instance, many people don't know that a child's toothpaste can have added carbohydrates and so can products such as lotions, sunscreens and even baby wipes," says Dr. Said.

Parents should encourage carbohydrate-free fluids to help their child stay hydrated – and should also watch for foods packaged as low carb such as low-carb sweeteners in a powdered form – these often contain hidden carbs too. Some snacks and vegetable juices packaged as healthy may appear that way, but these can often contain hidden sugars. Make sure to check the nutrition labels for any added carbs.

Transitioning to and managing a ketogenic diet can be challenging, but it may provide life-changing relief from seizures for some children. Talk to your child's epilepsy care team for more information and for other ways to support your child through this dietary therapy.

Learn more

Designated as a Level 4 Epilepsy Center by the National Association of Epilepsy Centers, Children's Medical Center Dallas provides the highest level of treatment for the most complex cases of pediatric epilepsy, with additional advanced epilepsy treatment options available at our Level 3 Epilepsy Center in Plano. Learn more about our program and services.

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