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UPDATE: Reports Suggest Vitamin D Supplements Do Not Reduce Ongoing MS Disease Activity

April 19, 2023

Update to Bulletin posted 10/27/22
UPDATE: Results from the U.S.-based study have now been published - see below.
-- These studies do not answer whether vitamin D can prevent MS

At the 2022 ECTRIMS (European Committee for the Treatment and Research of Multiple Sclerosis) conference in Amsterdam this week, results of two vitamin D supplement trials were announced. Both studies suggest that high doses of vitamin D do not reduce MS disease activity. 
These studies were undertaken because studies suggest that having low blood levels of vitamin D increases the risk of getting MS, and it was not known whether people who already have MS can reduce disease activity by taking vitamin D supplements.
There are Still Questions
  • Since participants in these studies did not have severe vitamin D deficiencies at the beginning of the study, we don’t know whether people with severe vitamin D deficiency would receive any benefit from vitamin D supplements.
  • These studies do not tell us whether vitamin D supplements can prevent MS from developing before any symptoms occur, including people who may be at higher risk for MS because of a family history of the disease.
  • Additional studies of vitamin D supplementation are underway. When the results from these two studies and other studies are published in peer-reviewed medical journals, we should have further clarity to inform recommendations about the use of vitamin D supplements by people living with MS.
  • Having sufficient vitamin D is important for immune system function, bone health, and other bodily systems. Individuals who have questions about whether they have a vitamin D deficiency and whether they should consider taking supplements should consult their primary care physician or MS healthcare clinician.
U.S. Study
  • A clinical trial conducted by Dr. Ellen Mowry of Johns Hopkins University and colleagues across the country compared high doses (5000 International Units per day) versus low doses (600 International Units per day) of vitamin D supplements in people with relapsing-remitting MS who were taking daily injections of Copaxone (glatiramer acetate, supplied by Teva Neuroscience, Inc).
  • After 96 weeks, among 140 people who completed the trial, the was no evidence that high-dose vitamin D supplements reduced MS activity, including relapses and MRI-detected brain lesions.
  • This study was funded by the National MS Society. Teva Neuroscience, Inc. provided Copaxone for the duration of the trial.
UPDATE: Full results from this study have now been published in eClinicalMedicine and can be accessed by anyone without a subscription.

Australia-New Zealand Study
  • A clinical trial conducted by Dr. Helmut Butzkueven and other investigators in Australia and New Zealand tested multiple dose levels (1,000, 5,000, or 10,000 International Units per day) compared to inactive placebo in 204 people who had be diagnosed with clinically isolated syndrome (CIS) and who were not being treated by an MS disease-modifying therapy. (People with CIS have experienced a first episode of a neurological symptom that may or may not develop into definite MS.)
  • The trial tested whether any dose of vitamin D could delay the onset of definite MS.
  • After 48 weeks, the investigators found no difference in the number of people in each treatment arm who went on to develop definite MS.
  • This trial was funded by MS Australia, with additional support from the National MS Society.
Learn more about vitamin D and MS
These trials would not have been possible without the volunteer participation of people living with MS. Learn more about participating in MS research
Stay tuned for a summary of research news from ECTRIMS. In the meantime, anyone can explore the program and the brief summaries (abstracts) of presentations

About Multiple Sclerosis

Multiple sclerosis is an unpredictable, often disabling disease of the central nervous system. Symptoms range from numbness and tingling to blindness and paralysis, and there is currently no cure for MS. The progress, severity and specific symptoms of MS in any one person cannot yet be predicted, but advances in research and treatment are leading to better understanding and moving us closer to a world free of MS. An estimated 1 million people live with MS in the United States. Most people with MS are diagnosed between the ages of 20 and 50, and it affects women three times more than men.


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