VITAMIN D3 IN THE PATHOGENESIS AND CLINICAL COURSE OF MULTIPLE SCLEROSIS: A COMPREHENSIVE REVIEW OF CURRENT EVIDENCE (2015–2026)
DOI:
https://doi.org/10.31435/ijitss.1(49).2026.5069Keywords:
Multiple Sclerosis, Vitamin D3, Mendelian Randomization, MRI Activity, Randomized Controlled Trials, NeuroimmunologyAbstract
Multiple sclerosis (MS) is a chronic immune-mediated demyelinating disease of the central nervous system characterized by inflammatory activity, neuroaxonal degeneration, and progressive neurological disability. Over the past decade, converging epidemiological, genetic, and mechanistic evidence has positioned vitamin D3 as a biologically plausible environmental determinant influencing MS susceptibility and potentially modulating disease course. This comprehensive review synthesizes peer-reviewed literature published between 2015 and 2026, including Mendelian randomization analyses, large-scale genomic studies, randomized controlled trials, and contemporary meta-analyses. Independent Mendelian randomization studies consistently demonstrate that genetically determined lower circulating 25-hydroxyvitamin D concentrations increase the risk of MS, supporting a causal role in disease susceptibility. In contrast, randomized supplementation trials in established relapsing–remitting MS report heterogeneous and generally modest effects on relapse rates, MRI activity, and disability progression. Emerging data from early-stage disease, including clinically isolated syndrome, suggest a potential stage-dependent benefit. Collectively, current evidence indicates that vitamin D functions primarily as a susceptibility modifier and early immunological regulator rather than a definitive disease-modifying therapy in established MS. Future research should prioritize early-life exposure, genotype-informed stratification, and long-term clinical outcomes to clarify the translational potential of vitamin D optimization in multiple sclerosis.
References
Ascherio, A., & Munger, K. L. (2016). Epidemiology of multiple sclerosis: From risk factors to prevention—An update. Seminars in Neurology, 36(2), 103–114. https://doi.org/10.1055/s-0036-1579693
Dörr, J., Bäcker-Koduah, P., Wernecke, K. D., Becker, E., Hoffmann, F., Faiss, J., Brockmeier, B., Hoffmann, O., Anvari, K., Wuerfel, J., Piper, S. K., Bellmann-Strobl, J., Brandt, A. U., & Paul, F. (2020). High-dose vitamin D supplementation in multiple sclerosis—results from the randomized EVIDIMS (efficacy of vitamin D supplementation in multiple sclerosis) trial. Multiple Sclerosis Journal—Experimental, Translational and Clinical, 6(1), 2055217320903474. https://doi.org/10.1177/2055217320903474
Doosti-Irani, A., Tamtaji, O. R., Mansournia, M. A., Ghayour-Mobarhan, M., Ferns, G., Daneshvar Kakhaki, R., Rezaei Shahmirzadi, A., & Asemi, Z. (2019). The effects of vitamin D supplementation on expanded disability status scale in people with multiple sclerosis: A critical, systematic review and meta-analysis of randomized controlled trials. Clinical Neurology and Neurosurgery, 187, 105564. https://doi.org/10.1016/j.clineuro.2019.105564
Fitzgerald, K. C., Munger, K. L., Köchert, K., Arnason, B. G., Comi, G., Cook, S., Goodin, D. S., Filippi, M., Hartung, H. P., Jeffery, D. R., O’Connor, P., Suarez, G., Sandbrink, R., Kappos, L., Pohl, C., & Ascherio, A. (2015). Association of vitamin D levels with multiple sclerosis activity and progression in patients receiving interferon beta-1b. JAMA Neurology, 72(12), 1458–1465. https://doi.org/10.1001/jamaneurol.2015.2742
Hupperts, R., Smolders, J., Vieth, R., Holmøy, T., Marhardt, K., Schluep, M., Killestein, J., Barkhof, F., Beelke, M., Grimaldi, L. M. E., & SOLAR Study Group. (2019). Randomized trial of daily high-dose vitamin D3 in patients with RRMS receiving subcutaneous interferon β-1a. Neurology, 93(20), e1906–e1916. https://doi.org/10.1212/WNL.0000000000008445
International Multiple Sclerosis Genetics Consortium. (2019). Multiple sclerosis genomic map implicates peripheral immune cells and microglia in susceptibility. Science, 365(6460), eaav7188. https://doi.org/10.1126/science.aav7188
Mahler, J. V., Solti, M., Apóstolos-Pereira, S. L., Adoni, T., Silva, G. D., & Callegaro, D. (2024). Vitamin D3 as an add-on treatment for multiple sclerosis: A systematic review and meta-analysis of randomized controlled trials. Multiple Sclerosis and Related Disorders, 82, 105433. https://doi.org/10.1016/j.msard.2024.105433
Mokry, L. E., Ross, S., Ahmad, O. S., Forgetta, V., Smith, G. D., Goltzman, D., Leong, A., Greenwood, C. M., Thanassoulis, G., & Richards, J. B. (2015). Vitamin D and risk of multiple sclerosis: A Mendelian randomization study. PLoS Medicine, 12(8), e1001866. https://doi.org/10.1371/journal.pmed.1001866
Olsson, T., Barcellos, L. F., & Alfredsson, L. (2017). Interactions between genetic, lifestyle and environmental risk factors for multiple sclerosis. Nature Reviews Neurology, 13(1), 25–36. https://doi.org/10.1038/nrneurol.2016.187
Rhead, B., Bäärnhielm, M., Gianfrancesco, M., Mok, A., Shao, X., Quach, H., Shen, L., Schaefer, C., Link, J., Gyllenberg, A., Hedström, A. K., Olsson, T., Hillert, J., Kockum, I., Glymour, M. M., Alfredsson, L., & Barcellos, L. F. (2016). Mendelian randomization shows a causal effect of low vitamin D on multiple sclerosis risk. Neurology: Genetics, 2(5), e97. https://doi.org/10.1212/NXG.0000000000000097
Thouvenot, E., Laplaud, D., Lebrun-Frenay, C., Derache, N., Le Page, E., Maillart, E., Froment-Tilikete, C., Castelnovo, G., Casez, O., Coustans, M., Guennoc, A. M., Heinzlef, O., Magy, L., Nifle, C., Ayrignac, X., Fromont, A., Gaillard, N., Caucheteux, N., Patry, I., De Sèze, J., … D-Lay MS Investigators. (2025). High-dose vitamin D in clinically isolated syndrome typical of multiple sclerosis: The D-Lay MS randomized clinical trial. JAMA, 333(16), 1413–1422. https://doi.org/10.1001/jama.2025.1604
Walton, C., King, R., Rechtman, L., Kaye, W., Leray, E., Marrie, R. A., Robertson, N., La Rocca, N., Uitdehaag, B., van der Mei, I., Wallin, M., Helme, A., Angood Napier, C., Rijke, N., & Baneke, P. (2020). Rising prevalence of multiple sclerosis worldwide: Insights from the Atlas of MS, third edition. Multiple Sclerosis Journal, 26(14), 1816–1821. https://doi.org/10.1177/1352458520970841
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Copyright (c) 2026 Martyna Jaciubek, Maja Osuch, Maciej Osuch, Olga Tatarata, Carmena Luty, Amanda Abramowicz, Magdalena Rumin, Anna Kiełboń, Zuzanna Olga Reklewska, Kornelia Domagała

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