French researchers conducted clinical trials and found that high doses of vitamin D significantly reduce the likelihood of progression of the onset of multiple sclerosis for at least two years. The study was published in The Journal of the American Medical Association.
Vitamin D deficiency is a significant risk factor for the development and progression of multiple sclerosis. However, existing data on the potential benefits of vitamin D supplementation are insufficient and contradictory.
Eric Thouvenot of the University of Montpellier and colleagues conducted a double-blind, randomized, controlled phase III trial of D-Lay MS at 36 French clinical centers from 2013 to 2023. They enrolled 316 patients aged 18–55 years (median 34 years; 70 percent women; 288 completed the trial) with clinically isolated syndrome (CIS; the first episode of neurological symptoms characteristic of multiple sclerosis), serum vitamin D levels less than 100 nanomoles per milliliter, and MRI evidence of the disease. Half of the participants were given 100,000 international units of cholecalciferol (the active form of vitamin D) orally every other week for two years; the other half received a placebo.
At month 24, disease activity was recorded in 60.3 percent of participants in the main group versus 74.1 percent in the control group (odds ratio 0.66; p = 0.004). The median time to the onset of this activity was longer with cholecalciferol: 432 versus 224 days (p = 0.003). The main group also had lower rates of MRI disease activity (p = 0.02), new MRI lesions (p = 0.003), and contrast-enhancing lesions (p = 0.001). The results were similar when analyzing a subgroup of 247 patients who met the 2017 updated diagnostic criteria for relapsing-remitting multiple sclerosis at trial inclusion. No severe treatment-related adverse events were recorded.
Thus, high doses of vitamin D significantly reduce disease activity in CIS and early relapsing-remitting multiple sclerosis and deserve further study as an additional high-dose pulse therapy for the disease, the authors conclude.
Previously, Swedish scientists conducted a population-based case-control study and concluded that a high fish content in the diet of patients with multiple sclerosis is associated with a lower risk of disability and the progression of the disease to its most severe forms.
