Vitamin D in Multiple Sclerosis and Central Nervous System Demyelinating Disease—A Review

BACKGROUND: The role of vitamin D as both a risk factor and a disease modifier in multiple sclerosis (MS) has a storied history with ongoing accumulation of supportive convergent evidence from animal data, clinical studies and trials, and biomarkers of disease. EVIDENCE ACQUISITION: A detailed review of the published literature ranging from in vivo immune studies to human clinical studies of epidemiology, physiology, immunology, clinical, and radiological markers was undertaken. RESULTS: There is compelling evidence that vitamin D is not only a risk factor for central nervous system (CNS) demyelinating disease (namely MS) but also seems to modify both the inflammatory and neurodegenerative elements of the disease, with large-scale treatment trials underway. The authors also address questions of interest that remain unanswered. CONCLUSIONS: Vitamin D is an important contributor and modifiable risk factor in CNS demyelinating disease. Further work will determine whether it is also neuroprotective and if such benefits will apply to other inflammatory and degenerative neurological diseases.