Online Health Chat with Ahsan Moosa Naduvil Valappil, MD

January 8, 2014


In the United States, epilepsy affects approximately 2.5 million people of all ages and backgrounds. Although many advances have been made in the diagnosis and treatment of epilepsy, about one third of patients continue to have epilepsy that remains difficult to control despite multiple medications. Some of these patients may benefit from epilepsy surgery. In others, research has shown that seizures may be controlled through a stringent medically supervised diet such as the ketogenic diet—which is effective in some children as well as adults.

When medical treatment is ineffective and surgery cannot be performed, the ketogenic diet is an option. The ketogenic diet is a high-fat, low-carbohydrate regimen that needs to be implemented by a team of experienced dieticians and physicians. An important requirement for beginning the diet is commitment to the plan, as the diet requires extra time and effort.

Nearly 50 percent of children on the ketogenic diet experience greater than 50 percent reduction in seizures. And nearly 10 percent of these patients will have greater than 90 percent reduction in seizures. However, the dedication to maintaining the ketogenic diet starts at the beginning. This plan needs to be followed for at least three months to decide whether if it is of benefit or not. An added benefit of the ketogenic diet is that many parents and caregivers report that children are more alert on the diet. If the diet seems to be beneficial to the child, doctors will usually prescribe it for about two years.

Children on the ketogenic diet plan will experience a decrease in seizures, but usually need to continue taking antiseizure medicine—although they may be able to take less of it later on. Children who respond exceptionally well may be advised to slowly taper seizure medication with the goal of discontinuing it altogether.

About the Speaker

Ahsan Moosa Naduvil Valappil, MD, is a pediatric epileptologist who treats children and adolescents at Cleveland Clinic's Epilepsy Center in the Neurological Institute at Cleveland Clinic. Dr. Naduvil is board certified in Neurology with Special Qualifications in Child Neurology, and Clinical Neurophysiology with added competency in Epilepsy Monitoring by the American Board of Clinical Neurophysiology and Pediatrics. His specialty interests include ketogenic diet therapy, medical and surgical treatment of epilepsy, hemispheric epilepsy syndrome and hemispherectomy/hemispherotomy, Rasmussen encephalitis, autoimmune epilepsy, genetic and metabolic causes of epilepsy, video EEG monitoring and invasive EEG monitoring.

Dr. Naduvil completed fellowships in child neurophysiology, EEG and epilepsy, as well as pediatric neurology, at Cleveland Clinic. He completed additional training at Amrita Institute of Medical Sciences and Research Institute, in Cochin, Kerala, India and Trivandrum Medical College, University of Kerala, Trivandrum, Kerala, India, as well as a research fellowship and neurology training at Trivandrum Medical College. He completed his neurology residency at Sree Chitra Tirunal Institute of Medical Sciences and Technology in Trivandrum, Kerala, India. His pediatric residency was completed at Post Graduate Institute of Medical Education and Research, in Chandigarh, India. Dr. Naduvil completed medical school at Thanjavur Medical College, in Thanjavur, Tamilnadu, India.

Let’s Chat About Ketogenic Diet Plan in Epilepsy Management

Moderator: Welcome to our chat today about the management of epilepsy and the ketogenic diet. Thank you, Dr. Naduvil, for joining us today. Before we begin with the questions, let's discuss some general information about the ketogenic diet and the pediatric epilepsy program at Cleveland Clinic.

Ketogenic Diet Description

Jessie: Would you explain the ketogenic diet?

Ahsan_Moosa_Naduvil,_MD: The ketogenic diet is a special high-fat diet used to treat difficult-to-control epilepsy. The ketogenic diet is a combination of high fat (90 percent of calories), very low carbohydrate (about one to two percent of calories) and optimum protein diet (optimized for body growth requirements). The total calorie requirement is calculated for the body weight and age (neither too low nor high). The total amount of fluids is not typically restricted.

SunnyV: What is the mechanism for why the ketogenic diet works? Does it work for any pediatric epilepsy patient or only specific ones?

Ahsan_Moosa_Naduvil,_MD: The exact mechanism how ketogenic diet works in epilepsy is not clear. There is debate between whether the high fat or the low glucose is the major factor in seizure control. It is possibly a combination of both. Switching energy course of brain cells from glucose to ketones and fatty acids (from the fats) seems to alter the excess excitability of the brain cells.

Ketogenic Diet vs. Modified Atkins Diet

TLC_BSN: I am 35 years old and have been epileptic since birth. I have failed many medications. My current regimen is Zonegran® (zonisamide) and Onfi® (clobazam). Onfi® is a new addition, and my neurologist is suggesting the ketogenic diet. How strict does one need to follow the ketogenic diet to gain maximum benefit? As a nurse along with being a full-time Masters of Nursing student, I have horrible work and sleep patterns. After reading a paper for a school project on artificial sweeteners enhancing seizures, I have cut out all diet sodas. I have noticed a huge difference.

Ahsan_Moosa_Naduvil,_MD: For you—and adults in general—the modified Atkins diet may be an option that is easier to practice. In the modified Atkins diet, the amount of carbohydrates per day is strictly controlled. The effect of any diet is usually obvious in the initial three months, assuming seizures are frequent enough to see a difference during this period. It is a good idea to follow the diet strictly during that period to see if the diet works for you. Otherwise you wouldn’t know if we tried the correct method. After that period, if you found the diet useful and are willing to continue, we may try to relax your carbohydrate intake and see how it impacts your seizures.

Michellelilly52: Could you please discuss the modified Atkins diet for seizure control and its efficacy? I have a teenage daughter with intractable epilepsy. She is on two medications and her seizures aren't under control. I am thinking of trying this diet as it seems like it would be somewhat easier for a teenager to adhere to.

Ahsan_Moosa_Naduvil,_MD: I agree that the modified Atkins diet is easier to adhere to. The modified Atkins diet (MAD) restricts carbohydrates to 10 to 15 g per day while encouraging high fat foods. It is relatively easier to implement the diet as it does not involve weighing foods. The math that goes into the diet is mostly with the amount of carbohydrates that is allowed. Recent reports suggest efficacy similar to the traditional ketogenic diet. About 45 percent of patients experience greater than 50 percent reduction in seizures and nearly 30 percent report greater than 90 percent reduction in seizures.

BenEK: I have read that for adults a modified Adkins diet is similar to the ketogenic diet. Why is this? Why not just have adults follow a ketogenic diet?

Ahsan_Moosa_Naduvil,_MD: There is no good real scientific reason for not doing a traditional ketogenic diet in adults since a benefit in adults has been reported in some studies. In my mind, the diet is a worthwhile option for patients with a high seizure burden, which is typically more common in children. As seizure reduction—rather than seizure freedom—is often the outcome with diet, many adults may not find it worth the effort— especially when seizure frequency is not as high as in some children with resistant epilepsy. Also, we often worry about issues like high cholesterol in adults more often than in children.

Duration of Ketogenic Diet

apike: What is the average length of time a person is on the ketogenic diet?

Ahsan_Moosa_Naduvil,_MD: It depends on the success of the diet. Anyone willing to try the diet should commit for a trial of at least three months. The duration of the diet depends on the efficacy, tolerability and side effects, as well as the natural course of underlying epilepsy. In patients who are seizure free and tolerating the diet well, weaning from the diet may be considered after two years. In others, the duration is variable. Typically, the patient who benefits from ketogenic diet achieves maximum benefits in the initial one to two years. In poor responders, diet may be tried for three to six months before being considered as a failure.

rmoore: I have a question about your statement, "Duration of the diet depends on the efficacy, tolerability and side effects and the natural course of underlying epilepsy. In patients who are seizure free and tolerating the diet well, weaning from diet may be considered after two years. In others, the duration is variable." How long can a patient stay on the ketogenic diet if they can't wean off, and still have a positive effect?

Ahsan_Moosa_Naduvil,_MD: Systematic use of the ketogenic diet started in the mid- 1990s. Long-term studies have reported patients on the diet for four to six years. There are anecdotal reports (personal communication) of being on the diet for more than 10 years. Obviously, these individuals did not have any significant side effects, and found the ketogenic diet very beneficial. But these patients are rare.

Robb: If the diet works for seizure reduction, does it have to be followed for a long period of time or forever?

Ahsan_Moosa_Naduvil,_MD: As a first step, we like to treat ketogenic diets like any other anti-seizure medication. If the diet is successful in making someone completely seizure free, then weaning after two years of treatment is appropriate. The long-term seizure freedom in a given individual often depends on the primary condition that led to epilepsy.

kcooke: I am the health educator at the Epilepsy Foundation of Northeastern NY and we're hoping to add the ketogenic diet to our conference this year. How have you been able to encourage parents to try the diet and keep with the diet for a minimum of three months? Is there a high drop off rate?

Ahsan_Moosa_Naduvil,_MD: I agree that it is particularly difficult in relatively new-onset epilepsy patients who quickly fail several medications to get them to stick to the diet. The frequent seizures often force them to try other medications, and we lose the ability to confidently state the diet is the reason for improved seizure control on follow up. For patients with longstanding epilepsy, they are usually committed to trying the ketogenic diet. On average 10 to 20 percent of patients may not complete the full three-month trial of the diet.

Ketogenic Diet Success Rate

abm3: What is the success rate of the diet in patients who start on the ketogenic diet younger than five years old?

Ahsan_Moosa_Naduvil,_MD: Most of the data on traditional ketogenic diet are from studies in young children. About 50 percent of patients have greater than 50 percent reduction of seizures after three to six months on the ketogenic diet. Half of these may be significantly improved. Overall, one third of patients have major improvement (i.e., seizure-free or more than 90 percent reduction in seizures) after following the ketogenic diet. Other benefits reported by some families include improvement in alertness and responsiveness. Some families consider this as a success, and may plan to stay on the diet even if seizures are only marginally better.

Seizure Recurrence After Ketogenic Diet Completion

abm3: Have any studies shown a return or an increase in seizures after a patient has successfully completed the diet?

Ahsan_Moosa_Naduvil,_MD: Typically, the long-term seizure freedom depends on the primary reason that caused epilepsy. In some retrospective studies, about 20 percent of patients had recurrence of seizures after weaning the diet. These patients were seizure free on the ketogenic diet and some also took additional medications. More than half of these patients regained seizure control with reinstating the diet or medication changes.

Side Effects of Ketogenic Diet

Robb47: Are there side effects when you start the ketogenic diet? Can it be started at home or does the child or adult need to be in the hospital to be medically supervised?

Ahsan_Moosa_Naduvil,_MD: As with any medical therapy, ketogenic diet also has a few side effects. Usually changes in the regimen may alleviate many of the side effects. Common side effects include: constipation slowed growth, hypoglycemia and acidosis (increased body acid levels) during acute illness.

Less common side effects include gastrointestinal reflux (GERD), excessive or inadequate ketosis (use of fats for energy), growth restriction due to high cholesterol (a quarter of children may have levels above 300) and low bone density. During the initiation phase of the diet, there is a risk of low blood sugar. With regard to cholesterol problems an occasional patients may have levels greater than 500 mg . Lowering the ratio or changing of the type of fats may be tried. There are no reports of vascular events such as heart attack or stroke from the ketogenic diet. Other rare side effects include kidney stones and trace element deficiency (selenium). The addition of Cytra-K® crystals (potassium citrate and citric acid) has dramatically reduced the chance of kidney stones. Patients are routinely supplemented with vitamins and minerals to avoid micronutrient deficiency.

Any diet therapy for epilepsy should be done under medical supervision and should not be done solely by the patient or family. Only the patient who is treated with the traditional ketogenic diet needs hospitalization for three to five days to monitor for side effects at the beginning of the diet. Some centers start the traditional diet slowly as an outpatient though.

CMB: Are there any concerns of the diet helping to control seizures, but causing other health problems?

Ahsan_Moosa_Naduvil,_MD: As with any therapy we have to weigh the benefits vs. the risks. Many of the common side effects are relatively benign.

sciencenow: Are there side effects associated with reintroducing the child to a normal diet?

Ahsan_Moosa_Naduvil,_MD: With regard to reintroducing a normal diet, it is pretty benign. Depending on the success of the diet and prior duration of diet, we may do it slowly (similar to weaning of anti-seizure medications).

Ketogenic Diet Treatment Recommendations

Noname: Are there certain types of seizures where the ketogenic diet is more effective?

Ahsan_Moosa_Naduvil,_MD: Children with generalized seizures, particularly infantile spasms and drop seizures, benefit more from the diet. There are particular conditions in which the diet works better, such as infantile spasms, Doose syndrome (myoclonic astatic epilepsy, or MAE), pyruvate dehydrogenase deficiency, Rett syndrome, and tuberous sclerosis complex. In a rare metabolic disorder called GLUT1 (glucose transporter type 1) deficiency in which glucose transport from blood to the brain is defective, the ketogenic diet is the treatment of choice to provide energy to the brain. In short, diet may be considered for anyone with resistant epilepsy with frequent seizures.

loveitaly: My daughter is 32 years old. She has cerebral palsy, seizure disorder from birth, scoliosis, hypothyroidism, GERD (gastroesophageal reflux disease), etc. She is very sensitive and cannot tolerate the majority of anti-seizure meds due to the severity of their side effects. Many times, her seizures get worse. She only can take two or three medications, and sometimes she does better. When she is not, Ativan® (lorazepam) is her rescue medication at home. When she was a child, I consulted with the physicians. They said she was not a candidate for the ketogenic diet because she was already over 10 years old. She could have aspiration from fatty, oily foods that could easily locate in her lungs, in part because her seizures are complex partial and not generalized. (Even though she is 32 years old, she is petite in size and weight).She is generally healthy. Is the diet recommended for a person with her conditions and small weight and height even though she is an adult in age? I want to have your input as an adult neurologist because pediatric physicians think different.

Ahsan_Moosa_Naduvil,_MD: I am sorry to learn about your daughter's ongoing seizures. I am a pediatric epileptologist, but I also see adult patients who are willing to try diet. Of the three reasons you stated age is not a factor to decide whether dietary therapy can be beneficial. We often used a modified diets—specifically, the modified Atkins diet —for teenagers and adults. The ketogenic diet may increase the reflux problems, and aspiration may be a risk in susceptible individuals. However, it can be used in most seizure types if they are frequent and resistant to medical treatment. We avoid the ketogenic diet in patients who are malnourished. If your daughter's weight is appropriate for her height, the ketogenic diet is an option. I would recommend talking to your neurologist and seeking consultation for the same.

danot2: We were introduced to the ketogenic diet months ago but my son couldn’t get past the fasting period. Do you think this is a failed attempt or should we try it again?

Ahsan_Moosa_Naduvil,_MD: It sounds like a failed attempt, but I am not sure what you mean by "couldn’t get past the fasting period." Some centers start the ketogenic diet without much fasting.

Ketogenic Diet and Medications

Erik: Does the ketogenic diet increase the risk of kidney stones and metabolic acidosis when used in combination with certain medications?

Ahsan_Moosa_Naduvil,_MD: Certain medications, such as Topimax® (Topiramate) and Zonegran® (zonisamide), increase the risk of acidosis and kidney stones. However, this does not occur to a significant extent in every patient. As the ketogenic diet independently can cause these side effects, it is a legitimate concern that the risks may be increased. In a small study from Johns Hopkins University School of Medicine, this was not confirmed (meaning there was no increased risk). However, I personally believe that it is a concern and we need to watch it closely. The addition of Polycitra-K® (citric acid and potassium citrate) as a supplement has significantly reduced the risk of kidney stones in ketogenic diet patient.

Ketogenic Diet Supplemental Information

Shane: Do you recommend a cookbook or online site that would offer meal planning for the ketogenic diet?

Ahsan_Moosa_Naduvil,_MD: We routinely use the website to plan the recipes. Our Cleveland Clinic dietician registers our patients to this website, and walks them through the process. All recipes have to be approved by the registered dietician to ensure compliance.

Exercise and the Ketogenic Diet

Margaret: Does the ketogenic diet have any impact on my child's ability to participate in extracurricular activities (such as bowling or painting)? Sometimes I feel her energy levels are down due to this diet plan.

Ahsan_Moosa_Naduvil,_MD: I suspect this may be a problem in some patients. It also depends on the type of exercise. The body typically depends on glucose and stored sugar (glycogen) for quick bursts of activity like a quick sprint of 100 meters. But activities, such as bowling and painting, where the energy needs are not that robust may not be an issue.

Ketogenic Diet Team

QT: I have read that children following a ketogenic diet should be monitored by a dietician, nurse and neurologist. My daughter regularly sees a child neurologist for her epilepsy and follows the diet, but was not recommended to see a dietician or other specialist. Is this something I should inquire about on our next visit?

Ahsan_Moosa_Naduvil,_MD: We have a team of three members who include an epileptologist, registered dietician and registered nurse. For the traditional ketogenic diet, I depend on my dietician to implement the diet. For modified diets, such as the modified Adkins diet or low glycemic index diet, a lot of expertise in dietetics may not be needed, but is preferred.

Ketogenic Diet for Other Medical Conditions

J40K: In an Internet search of the ketogenic diet, I see information about it being beneficial for cancer, weight loss and body building. What is your opinion? Are there studies to support these claims?

Ahsan_Moosa_Naduvil,_MD: My practice and expertise is limited to epilepsy. Losing weight is not the aim for our patients with epilepsy, but it may occur as a side benefit in patients who are overweight when we allow only the recommended calories. I am aware of some reports in other medical conditions, but I do not know more about it.


Moderator: I am sorry to say that we are at the end of our chat. We appreciate your participation and hope you will join us for other chat topics in the future. Thank you, Dr. Naduvil, for sharing your expertise and answering questions today.

Ahsan_Moosa_Naduvil,_MD: Remember the ketogenic diet as an option for drug-resistant epilepsy. Anyone who fails two to three medication trials should be tested to see if the epilepsy can be cured by epilepsy surgery. If surgery is not an option, then one should consider diet therapy. It is likely to yield more benefits in someone with high-seizure frequency. Any diet therapy for epilepsy should be done under medical supervision and should not be done by the patient and family alone. It was nice chatting with all of you. Thanks for your participation.

For Appointments

To make an appointment with Ahsan Moosa Naduvil, MD, or any of the other specialists in Cleveland Clinic’s Epilepsy Center, please call 216.636.5860 or toll-free 866.588.2264.

For More Information

On Cleveland Clinic

At Cleveland Clinic's Pediatric Epilepsy Program, part of the Neurological Institute associated with Cleveland Clinic Children’s, we strive to meet the unique needs of each child with epilepsy. Each year, there are more than 2,000 pediatric epilepsy patient visits to our outpatient clinics. Advanced technology enables us to provide accurate diagnosis, effective treatment and improved quality of life.

The broad range of services offered by a unified group of pediatric epilepsy specialists makes ours one of the foremost programs of its kind in the world and among one of the only in the country that provides a well-rounded range of care for every pediatric epilepsy patient.

Our specialists oversee more than 2,000 pediatric epilepsy patient visits More than 500 children are evaluated each year in the Pediatric Epilepsy Monitoring Unit, which operates 24 hours a day, seven days a week. Cleveland Clinic was one of the first medical centers in the country to use specialized technology allowing physicians to determine the precise location of seizure activity in the brain. Patient outcomes are among the best in the country for a variety of epileptic syndromes. Our center has almost thirty years of experience performing epilepsy surgery.

Cleveland Clinic's Pediatric Epilepsy Program provides a well-rounded range of care through the latest in advanced imaging technologies, individualized medical management, rehabilitation services and support groups. The program works closely with the specialist from the Center for Pediatric Neurology and Neurosurgery.

The Neurological Institute at Cleveland Clinic is a leader in treating and researching the most complex neurological disorders, advancing innovations such as epilepsy surgery, stereotactic spine radiosurgery, interstitial thermal therapy for brain tumors and deep brain stimulation. The Institute combines physicians and other healthcare providers in neurology, neurosurgery, neuroradiology and behavioral sciences who treat adult and pediatric patients with a variety of neurological disorders.

Cleveland Clinic neurology and neurosurgery—pediatric and adult—are rated among the top ten hospitals in the United States by U.S.News & World Report, 2013-14.

Epilepsy Rehabilitation Services

If surgery is part of your child’s epilepsy treatment, we offer a comprehensive rehabilitation program through which each child receives an individualized, developmentally based treatment plan for physical, occupational and speech/language services.

A dedicated team of pediatric specialists, including doctors, nurses, rehabilitation specialists and psychosocial support staff works with the Epilepsy Center and each family to help children reach their full potential. Pediatric therapists work one-on-one with each child using state-of-the-art equipment specially designed for children.

Pediatric Epilepsy Support Groups

Our Pediatric Epilepsy Support Group meets regularly to address the needs of families who are caring for children afflicted with difficult-to-control epilepsy, or who have undergone, or are considering, epilepsy surgery. The group provides families an avenue to interact with epilepsy healthcare professionals, volunteers who have knowledge of the unique challenges of pediatric epilepsy, as well as each other. In this venue, families can share their thoughts, emotions and experiences.

Every other year, our Pediatric Epilepsy Support Group hosts a reunion for children who underwent epilepsy surgery at Cleveland Clinic, as well as their families. Physician-led conference sessions are offered to adult participants, while children will enjoy special activities, coordinated by a team of volunteers.

On Epilepsy Patient Education

Additional health information resources are available:

On Your Health

MyChart®: Your Personal Health Connection, is a secure, online health management tool that connects Cleveland Clinic patients with their personalized health information. All you need is access to a computer. For more information about MyChart®, call toll-free at 866.915.3383 or send an email to:

A remote second opinion may also be requested from Cleveland Clinic through the secure Cleveland Clinic MyConsult® website. To request a remote second opinion, visit

Reviewed: 01/14

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