Vitamin D and Seizure Control

Epilepsy News From: Tuesday, October 10, 2017

Vitamin D has been studied for decades for its many functions in the body. Vitamin D is essential to the development of bones during the growing years and maintenance of strong bones through adulthood. It’s also important in brain development and growth of new brain cells. 

Known as the “sunshine” vitamin, sunshine remains the best source for receiving vitamin D. Dietary sources include meat, fish, dairy products, and, interestingly, mushrooms. People who have little exposure to the sun are at increased risk for a vitamin D deficiency. Dark-skinned individuals are also at higher risk because the melanin in their skin blocks sun penetration.

Vitamin D May Help Seizure Control

Some anti-seizure medications interfere with how vitamin D is processed in the body. Supplemental vitamin D may be necessary for people who have these risk factors to maintain normal blood levels. 

A study published in 2012 showed that correcting vitamin D deficiency reduced seizures in people with epilepsy.1 Only 1 of the 13 people in the study had sufficient vitamin D levels at the start of the study. All were provided with supplemental vitamin D based on their blood levels. Each person was checked during the study to make sure that the vitamin D levels normalized and didn’t become toxic. Seizures were recorded 90 days before and after individuals received the supplemental vitamin D. 

Research in animals has also shown that vitamin D may play a role in seizures.

Study Results

The study included the following results:

  • 10 of the 13 participants experienced fewer seizures with vitamin D supplements. 
  • 2 of the 13 experienced more seizures and 1 had no change. 
  • 5 of the 13 experienced a 50% or greater reduction in overall seizures from baseline.

Although the study is small, it suggests a major vitamin D deficiency may play a role in seizure control.

Vitamin D and SUDEP

In addition to potential seizure control, there is preliminary evidence that vitamin D may also play a role in sudden unexpected death in epilepsy (SUDEP). In a large cardiovascular health study of 2,300 people, sudden cardiac death was twice as high (2 vs. 4 deaths in 1,000 people) for those with vitamin D levels below 20 ng/dl compared to individuals with levels above 20 ng/dl.2 One possible cause of SUDEP is irregular heart rhythm.

Check Your Levels

The Charlie Foundation recommends that everyone who has epilepsy have their 25-hydroxy vitamin D level checked. Review the following levels for 25-hydroxy vitamin D before speaking with your healthcare provider:

  • Deficient: <25 ng/ml
  • Optimal: 25-80 ng/ml
  • Toxicity: >80 ng/ml

Multiply ng/mL by 2.5 to convert to nmol/liter.

More Information on Seizures and Nutrition


  1. Hollo A. Correction of vitamin D deficiency improves seizure control in epilepsy: A pilot study. Epilepsy Behavior (2012) 24:131-3.
  2. Drechsler C. Vitamin D deficiency is associated with sudden cardiac death combined with cardiovascular events and mortality in hemodialysis patients. Eur Heart J (2010) 31:2253-61.
  3. Kennel KA, Drake MT, Hurley, DL. Vitamin D deficiency in adults: When to test and how to treat. Mayo Clinic Proceedings (2010) 85(8): 752-758. 

Authored by

Beth Zupec-Kania RDN, CD

Reviewed Date

Tuesday, October 10, 2017

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