"It is believed that the active form of vitamin D has immunomodulatory effects on cells of the immune system, particularly T lymphocytes, as well as on the production and action of several cytokines" Rev Bras Reumatol 2010 Feb;50(1):67-80
Vitamin D has come a long way in the past decade. We used to appreciate vitamin D for its role in promoting calcium absorption at the gut. This is still the case, but we now see that vitamin D has so many more exciting roles in the body. One of the most intriguing is its role in modulating the immune system.
Let's remember that nearly 3/4 of Americans have low levels of vitamin D. Experts universally agree that raising vitamin D levels is essential for optimal health. There is some disagreement as to the dosage required, use of sunlight, tanning beds or fortified foods. But we all agree that low vitamin D levels are not good and may manifest in a number of different ways.
"A growing body of evidence supports a role for vitamin D in MS aetiology."J Neurol 2010 Nov 2.
"...it would appear likely that hypovitaminosis D is one of the risk factors for multiple sclerosis." Brain 2010 Jul;133(Pt 7):1869-88.
"Experimental animal models of MS reproduce the beneficial effects of vitamin D..." Nutr Rev 2008 Oct;66(10 Suppl 2):S135-8.
The list goes on and on with general agreement that vitamin D deficiency is a very serious issue with respect to the cause and progression of multiple sclerosis.
Vitamin D levels can be easily assessed. While 25 OH levels are typically the vitamin D form that are measured in blood, it may be worthwhile to also measure 1,25 dihydroxy vitamin D, the active form of vitamin D. Closely monitor these levels as people may respond differently to the same dose. If you have MS, it is in your best interest to maintain healthy levels of vitamin D.