Low Carbohydrate Diets Effective Against Epileptic Seizures
Diets low in carbohydrates and high in fat, such as the ketogenic diet or the new Atkins diet, reduce the frequency of seizures in people with drug-resistant epilepsy.
The ketogenic diet is a therapeutic regimen used for several decades to treat epilepsy, especially in children (before there are drugs and then for those in which they do not act). There is now evidence that this diet works in adults, refractory to antiepileptics (about 35% of patients).
Why follow a ketogenic or low carb diet
In the ketogenic diet, the low amount of dietary carbohydrates leads the liver to metabolize fats in the form, among others, of ketone bodies (beta-hydroxybutyrate, acetoacetate, acetone) and therefore to use fats as a source of energy, rather than carbohydrates. This fuel change seems to have beneficial effects for the brain. Without really knowing the mechanisms by which they act, these ketone bodies relieve epileptics, reducing attacks by at least half. They would modulate brain excitability.
The new Atkins diet is a low carb diet less restrictive than the ketogenic diet (except in its attack phase). It appears to have effects similar to the ketogenic diet in epileptics, in a modified version (1).
The foods allowed in these two dietary patterns are: all fats, meats, poultry, fish, eggs, cheeses, cream, nuts and seeds, green leafy vegetables and most starchy vegetables. Overall, the ketogenic diet corresponds to a 3: 1 or 4: 1 ratio between fats and the protein + carbohydrate combination, that is to say that 87 to 90% of calories come from fat. In the modified Atkins diet (for epileptics), 50 to 65% of the calories come from fat and the ratio between fat and protein and carbohydrate duo is close to 1: 1.
What studies say
In epileptic children who do not respond to medication, the ketogenic diet reduces seizures by more than 50% for about 40% of children and suppresses them to 90% or completely in 7 to 15% of cases (2). Results similar to those obtained with drugs. In children, overall, the ketogenic diet is recognized as very effective in reducing by at least 50% the number of attacks in 30 to 60% of patients. Despite this success in children, the ketogenic diet has been relatively little studied in adults.
In 2014, researchers from the American Academy of Neurology synthesized 5 studies of the ketogenic diet – involving 47 people in total – and 5 studies of the new Atkins diet including 85 people in total (3). The results show that 32% of those who followed the ketogenic diet and 29% of those who followed the Atkins diet found at least 50% decrease in their epileptic seizures. 9% of those who followed the ketogenic diet and 5% of those who followed the Atkins diet even achieved a decrease of more than 90% in the frequency of epileptic seizures.
In 2015, Chinese scientists conducted a meta-analysis of 12 studies and 270 patients refractory to drugs (4). They reached similar conclusions: an efficiency of the ketogenic diet (all types of diet combined) to reduce seizures by 42% on average (13 to 70% according to the studies), an efficiency of 52% for the strict ketogenic diet and 34% for the modified Atkins diet. If the success of the latter was less, people had less trouble following him than the ketogenic diet.
Overall, the results of the studies are still very heterogeneous and the quality of the tests does not allow a definitive conclusion yet.
Limits and future prospects
- Ketogenic diet or modified Atkins diet seem less effective in adults than in children, according to current knowledge, although their effects may be remarkable in some people.
- The benefit of dietary changes comes quickly – a few days or even weeks after the start of the diet. But unlike children, the effects of these two regimens on epileptic seizures do not continue when patients stop the diet.
- Among the side effects, the most serious is hyperlipidemia (which reverses when the diet stops) and the most common is weight loss that may be beneficial to some patients.
- Many people have abandoned the diet before graduation because of the sometimes difficult restrictions to follow.
- Scientists also have another area of concern: the strict ketogenic diet may in some cases result in metabolic acidosis. Chronic acidosis may increase the risk of epileptic seizures. English researchers therefore propose to slightly modify the ketogenic diet to limit the risk of acidosis (5). Their recommendations (to be confirmed by studies): avoid caloric restriction (to limit the rate of circulating ketones and thus acidosis), better control protein intake (stick to recommendations 0.8 g / kg / day) , increase the share of green leafy vegetables (salad, chard, spinach …) for their alkalizing effect, include a lemon a day in the diet for its citrate, take a supplement of magnesium citrate (citrate to dab the acidity and magnesium because it has anti-epileptic effects).
The ketogenic diet is also used against Alzheimer’s and in patients treated for cancer.
(1) Ghazavi A, Tonekaboni SH, Karimzadeh P, Nikibakhsh AA, Khajeh A, Fayyazi A. The ketogenic and atkins diets effect on intractable epilepsy: a comparison. Iran J Child Neurol. 2014 Summer;8(3):12-7.
(2) Neal, E.G., Chaffe, H.M., Edwards, N., Lawson, M., Schwartz, R., Fitzsimmons, G., Whitney, A., Cross, J.H., 2008. The ketogenic diet for the treatment of childhood epilepsy: a randomised controlled trial. Lancet Neurol. 7, 500–506
(3) Klein P1, Tyrlikova I2, Mathews GC2. Dietary treatment in adults with refractory epilepsy: A review. Neurology. 2014 Oct 29. pii: 10.1212/WNL.0000000000001004.
(4) Fang Ye, Xiao-Jia Li, Wan-Lin Jiang, Hong-Bin Sun, and Jie Liu : Efficacy of and Patient Compliance with a Ketogenic Diet in Adults with Intractable Epilepsy: A Meta-Analysis. J Clin Neurol. 2015 Jan;11(1):26-31.
(5) Alan W.C. Yuen, Isabel A. Walcutt, Josemir W. Sander : An acidosis-sparing ketogenic (ASK) diet to improve efficacy and reduce adverse effects in the treatment of refractory epilepsy. Epilepsy & Behavior 74 (2017) 15–21.