According to a pilot study from Johns Hopkins, taking a high dose of vitamin D3 is safe for people with multiple sclerosis and may help regulate the body’s hyperactive immune response.
Low blood levels of vitamin D are associated with an increased risk of developing multiple sclerosis (MS). People who have MS and low levels of vitamin D are more likely to have greater disability and more disease activity.
Study author Peter Calabresi, M.D., professor of neurology at the Johns Hopkins University School of Medicine, comments:
“These results are exciting, as vitamin D has the potential to be an inexpensive, safe and convenient treatment for people with MS. More research is needed to confirm these findings with larger groups of people and to help us understand the mechanisms for these effects, but the results are promising.”
The study involved 40 people with relapsing-remitting MS. Each received either 10,400 international units or 800 international units of vitamin D3 supplements per day for six months. Patients with severe vitamin D deficiency were not included in the study.
600 international units is the current recommended daily allowance of vitamin D3.
Blood tests at the start of the study and again at three and six months measured the amount of vitamin D in the blood and the response in the immune system’s T cells, which play a key role in MS.
Those taking the high dose had a reduction in the percentage of inflammatory T cells related to MS severity, specifically IL-17+CD4+ and CD161+CD4+ cells.
When the increase in vitamin D levels in the blood over base line levels was greater than 18 ng/ml, every additional 5 ng/ml increase in vitamin D led to a 1 percent decrease in the percentage of IL-17+CD4+ T cells in the blood. The people taking the low dose did not have any noticeable changes in the percentages of their T cell subsets.
Side effects from the vitamin supplements were minor and were not different between the people taking the high dose and the people taking the low dose. One person in each group relapsed.
Researchers are still determining the optimal level of vitamin D in the blood for people with MS. A suggested range of 40 to 60 nanograms per milliliter (ng/ml) has been proposed as a target.