Objective: To review and assess the role of vitamin D in the onset, progression, and relapse of multiple sclerosis (MS), based on evidence acquired from the analysis of preclinical, observational, and interventional studies.
Methods: All English language literature in MEDLINE (January 1969 through April 2012) was searched for observational and interventional studies on the dosage effect of vitamin D on the onset, progression, and relapse rate of MS. The medical subject heading (MeSH) terms used in the search included Vitamin D and Multiple Sclerosis.