J Neurol Neurosurg Psychiatry

Higher vitamin D intake linked to lower MS risk in large Norwegian cohort

January 16, 2026

This prospective cohort study of more than 78,000 Norwegian women found that higher vitamin D intake during pregnancy was associated with a 42% lower risk of developing multiple sclerosis (MS) over 14 years of follow‑up. Women in the highest quintile of vitamin D intake (median, 333 IU/day) had significantly reduced MS risk compared with those in the lowest quintile (hazard ratio, 0.58; 95% confidence interval, 0.38-0.89; P trend <0.01). The protective effect was observed for both dietary sources and supplements, with similar risk reductions for each. The findings support vitamin D itself—rather than sunlight—as a key modifier of MS risk.

Clinical takeaway: Encourage patients, especially those in low‑sunlight regions, to maintain adequate vitamin D intake through diet and supplements as part of MS risk reduction counseling.

Source:

Kapali A, et al. (2025, November 28). J Neurol Neurosurg Psychiatry. Vitamin D intake and multiple sclerosis risk in the Norwegian Mother, Father and Child cohort. https://pubmed.ncbi.nlm.nih.gov/41314793/