Vitamin D and Multiple Sclerosis: What the Research Suggests

A review published in Annals of Pharmacotherapy (Vol. 40, No. 6, pp. 1158–1161) examined decades of research (1970–2006) on the relationship between vitamin D and multiple sclerosis (MS). The authors found several studies suggesting that vitamin D supplementation may help improve MS symptoms. They also cited a large prospective cohort study in which higher vitamin D intake was associated with a 40% lower risk of developing MS.

Additional research has strengthened this connection:

  • Women and MS risk:
    A study in Multiple Sclerosis (2009; 15(1):9–15) evaluated 103 women with MS and 110 healthy controls. For women, every 10 mmol/L increase in 25-hydroxyvitamin D was linked to a 19% lower likelihood of having MS. Higher vitamin D levels were also associated with less severe disability.

  • Vitamin D levels in active-duty military personnel:
    A nested case-control study in the Journal of the American Medical Association (2006; 296(23):2832–2838) compared vitamin D levels in 251 U.S. military members with MS and 51 controls. Among white participants, those in the highest quintile of serum vitamin D had a 62% lower risk of MS compared to those in the lowest quintile. This association was not observed in Hispanic or African American participants.

Overall, these studies suggest that higher vitamin D levels may lower MS risk and potentially influence symptom severity, though responses may vary across populations.