Multiple sclerosis, or MS, is a progressive, inflammatory disease of your central nervous system, characterized by the patchy destruction of myelin in your brain and spinal cord. Myelin is the protective insulation that coats your nerve cells and permits normal conduction of electrical impulses. In 1960, scientists first recognized a connection between an increased incidence of MS and higher latitudes, suggesting a link between sunlight exposure, vitamin D-3 levels and multiple sclerosis. If you have MS, ask your doctor if vitamin D-3 supplementation is appropriate for you.
Immune Connection
According to researchers at Jacobs Neurological Institute in Buffalo, New York, MS is probably the result of an interaction between a variety of factors, including genetics, nutrition, sunlight exposure and infectious agents. Ultimately, the damage wrought on your nervous system is mediated by an inappropriate immune response that erodes the myelin from your nerves. By attaching to vitamin D receptors, or VDRs, on your immune cells, vitamin D may help to modulate this "autoimmune" activity.
Vitamin D Levels
The April 2011 issue of "Expert Review of Neurotherapeutics" cites several human studies that demonstrate an association between low vitamin D-3 levels and higher relapse rates in MS patients. One such study, published in the June 2005 edition of "Multiple Sclerosis," showed that vitamin D levels in most MS patients are high enough to maintain bone integrity, but during relapses these patients' vitamin D levels fall, indicating that the immune system may require higher levels of vitamin D to perform optimally.
Doses
Recommended dietary allowances for vitamin D3 -- the doses that prevent deficiency -- vary from 400 IU to 800 IU, depending on your age. The Institute of Medicine has established a tolerable upper intake level of 4,000 IU for adults, but clinical studies involving MS patients have demonstrated both tolerability and safety of much higher doses of vitamin D-3. A study published in the December 2010 issue of "PLoS One" employed daily doses of 20,000 IU of vitamin D-3 for 12 weeks without causing imbalances in calcium metabolism or other signs of toxicity. During another 2010 study conducted at the University of Toronto and involving 49 patients, doses up to 40,000 IU daily for 28 weeks, followed by daily doses of 10,000 IU for another 12 weeks, were found to be well-tolerated and safe.
Considerations
The cause of multiple sclerosis is unknown. Vitamin D-3, which is the form of vitamin D formed in your skin during sun exposure, exerts immune-modulating effects through its influences on VDRs in your cells, and high-dose vitamin D-3 has been shown to reduce relapse rates in MS patients. However, neither the optimal immune-modulating dose nor the maximum safe dose of vitamin D-3 has been determined. Vitamin D-3 doses exceeding the Institute of Medicine's tolerable upper limit are apparently safe for relatively short periods of time -- several months -- but the long-term safety of such doses is undetermined. Ask your doctor about the best vitamin D-3 dosage for you.
References
- "Acta Psychiatrica Scandinavica"; Some Comments on the Relationship of the Distribution of Multiple Sclerosis to Latitude, Solar Radiation, and other Variables; E.D. Acheson, et al.; November 1960
- "Expert Review of Neurotherapeutics"; Vitamin D and Multiple Sclerosis: Can Vitamin D Prevent Disease Progression?; B. Mehta, et al.; April 2011
- "Multiple Sclerosis"; 25-Hydroxyvitamin D Levels in Serum at the Onset of Multiple Sclerosis; M. Soilu-Hänninen, et al.; June 2005
- Linus Pauling Institute at Oregon State University: Vitamin D
- "PLoS One"; Safety and T Cell Modulating Effects of High Dose Vitamin D3 Supplementation in Multiple Sclerosis; J. Smolders, et al.; December 2010
- "Neurology"; A Phase I/II Dose-Escalation Trial of Vitamin D3 and Calcium in Multiple Sclerosis; J.M. Burton, et al.; June 2010
