Vitamin D & Seizures

An estimated 2 percent of adults experience a seizure during their lifetime, according to "The Merck Manual Home Health Handbook." While doctors know what may trigger the condition in some cases, half of all seizures have no known cause, according to the University of Maryland Medical Center. A growing body of scientific research suggests vitamin D may play a role in the occurrence and frequency of seizures.

Vitamin D

Vitamin D is necessary for the growth and maintenance of strong bones. The vitamin helps your body absorb calcium, reduces muscle weakness and improves immune system function. About 80 to 90 percent of your vitamin D intake comes from sunlight, according to MedlinePlus. Your body produces and stores this form of vitamin D, known as vitamin D-3 or cholecalciferol, when exposed to sunlight. Another important form of vitamin D, vitamin D-2 or ergocalciferol, is found in food. Good sources include fatty fish such as herring, tuna and salmon, eggs, cod liver oil, and vitamin-D-fortified cereals and dairy products. Low levels of vitamin D are linked to conditions such as osteoporosis, certain cancers, depression, obesity, diabetes, heart disease, multiple sclerosis and seizures.

Seizures

During a seizure, your brain malfunctions and transmits abnormal signals that may result in strange emotions, behaviors or sensations. You may also experience changes in alertness, vision changes, involuntary muscle twitching, uncontrollable shaking and even unconsciousness. The type of seizure you may have and your symptoms depend on the part of the brain affected. It is possible you may experience only one seizure in your lifetime or multiple seizures, often referred to as epilepsy. Brain injury, Alzheimer's disease, stroke, heart attack, meningitis, AIDS and other infectious diseases may trigger a seizure. Other triggers also include kidney or liver failure, illegal drugs, and abnormal sodium or glucose levels.

Vitamin D and Seizure Frequency

A landmark study by authors Claus Christiansen and colleagues in a 1974 issue of the "British Medical Journal" first reported the benefits of vitamin D supplementation among epileptic patients. According to the authors, patients who were given vitamin D-2 supplementation had fewer seizures after treatment than before treatment, while those who did not receive any vitamin D-2 saw no change in seizure frequency.

Anticonvulsants

Anticonvulsant medication, a first line of treatment for seizures, helps reduce the risk of having another seizure. The medication can also reduce the frequency of seizures in one-third of people who have them, according to "The Merck Manual Home Health Handbook." While effective, the medication may also lower levels of vitamin D in your body. When levels of vitamin D in your blood fall, calcium and phosphorous blood levels also drop, leading to muscle spasms and seizures.

Sunlight

Scientific research shows the frequency and severity of seizures is associated with sunlight exposure. A study of published research by S.A. Baxendale in the May 2011 issue of "Medical Hypotheses" found seizures occur more often in the winter and on dull overcast days and are more severe during winter months. The author notes the important role sunlight plays in the production and regulation of melatonin, a hormone some studies have found reduces the length and frequency of seizures.

Disease and Sudden Death

Vitamin D may reduce the risk of diseases that can cause seizures, according to the Vitamin D Council, a nonprofit educational organization. These diseases include HIV, AIDS, stroke, dementia and heart attack. A growing body of evidence also suggests arrhythmias, or abnormal heart rhythms that often occur during seizures, may increase the risk of sudden death in epileptic patients, Fulvio A. Scorza and colleagues report in a January 2010 issue of the journal "Medical Hypotheses."