If a child is taking high dosages of several antiepileptic drugs, tapering of one drug is started around the time the diet is started. If ketosis is maintained and seizure control improves, a further reduction in medications is often possible. Occasionally, all medications can be tapered and stopped. The carbohydrate content of medications, often significant in liquid formulations, must be considered in calculating total carbohydrates.
How successful is the diet?
After 1 year of therapy, approximately one third of patients experience a greater than 50% reduction in seizures (10% are seizure-free), one third have less than a 50% reduction, and one third are unable to tolerate the diet.
What are the possible complications of the diet?
The long-term effects of a high-fat diet, even if it is used for only several years, are unknown. Most experts believe benefits for brain development and intellectual and social functions with improved seizure control and reduced dosages of antiepileptic drugs outweigh the risks. Many parents worry about the potential effects of large amounts of dietary fat. Although the ketogenic diet raises “bad” lipids (VLDL and LDL) and lowers “good” lipids (HDL), there is no evidence of increased atherosclerosis in children or adolescents. Weight gain is not usually a problem because caloric intake is carefully supervised.
As previously discussed, the initial starvation period, if used, can cause very low blood sugar levels that require urgent treatment. Other potential problems include a deficiency of the vitamins B, C, and D; calcium; folate; and iron; therefore, these nutrients must be supplemented. The ketogenic diet often slows a child’s growth in height and weight, but this is often made up for, at least partially, when the diet is stopped. There is a risk of kidney stones, which can be reduced by adequate fluid intake. Although acetazolamide, topiramate, and zonisamide also predispose to kidney stones, they can still be used with good hydration by patients on the diet. Other complications include constipation and an increased risk of bone fractures.
How does the modified Atkins diet differ from the Atkins diet?
The modified form encourages more fat intake and less carbohydrate intake (10-30 g/day) than the original form.
What exactly is the low glycemic index?
The glycemic index is a measure of how quickly a carbohydrate increases the blood sugar level. Carbohydrates with a low glycemic index cause a slower and more gradual increase in blood sugar; those with a high glycemic index a cause more rapid increase in blood sugar. The low glycemic diet encourages carbohydrates with a low glycemic index (<55 on the index). These carbohydrates also have health benefits by reducing cholesterol and appetite and lowering the risk of diabetes and heart disease. The South Beach diet incorporates low glycemic carbohydrates into the diet. However, in contrast to the Atkins diet, which allows all types of fats, the South Beach diet encourages the healthier, unsaturated fats.
Where can I get more information?
The Internet provides a rich source of medical and parental wisdom (e.g., epilepsy.com, charliefoundation.org, matthewsfriends.org), but be wary of opinions from one individual or an unknown website. The Internet has everything from recipes and personal observations to supportive chat rooms. There are several informative books: The Ketogenic Diet: A Treatment for Children and Others with Epilepsy (by John Freeman et al., 2006), Keto Kid: Helping Tour Child Succeed on the Ketogenic (by Deborah Snider, 2006), and The Ketogenic Diet: A Complete Guide for the Dieter and Practitioner (by Lyle McDonald and Elzi Volk, 1998). The Ketogenic Cookbook (by Dennis and Cynthia Brake, 1997) provides valuable recipes.
The modified Atkins and low-glycemic diets are alternatives to the ketogenic diet. There have been no “head-to-head” comparisons with the ketogenic diet, but available data suggest that they have approximately the same effectiveness with fewer complications and problems. When compared to the ketogenic diet, these diets do not restrict protein intake, total calories, or fluids. They do not require hospitalization, initial fast, or careful calculations and weighing of food. As with the ketogenic diet, both diets produce ketosis; therefore, it can be helpful to monitor urinary ketones with indicator strips. Additionally, these diets are usually much easier for patients to comply with. Finally, the Atkins and low glycemic diets are used by millions of people for weight loss and for diabetes — there is a lot of information about them.
The major advantage of these diets over the ketogenic diet is that they are more like a normal diet, improving tolerability. The unrestricted protein intake is healthier for growing children. Also, although the modified Atkins and low-glycemic diets do not require the high fat content of the ketogenic diet that may accelerate atherosclerosis, the modified Atkins does encourage fat intake. These diets should ideally be used under the supervision of the doctor and with input from a dietician. Weight and height should be monitored, as well as cholesterol and triglyceride levels due to increased fat intake. Possible side effects include weight loss (which may be good!) and, for the modified Atkins diet, elevated cholesterol levels. It is uncertain if kidney stones are increased.