A recent study of people with relapsing remitting multiple sclerosis (RRMS) found that high-dose oral vitamin D3 supplementation did not influence markers of inflammation. Inflammation is a reaction to bodily injury that may be over-activated in people with multiple sclerosis (MS). The article, titled “Vitamin D supplementation and systemic inflammation in relapsing-remitting multiple sclerosis“ appeared October 1, 2015 in the Journal of Neurology.

In MS the body attacks its own myelin, a fatty substance that covers nerve cells and allows them to conduct impulses. Damage to myelin results in loss of movement, vision, sensory problems and other medical problems. Some research suggests that vitamin D can reduce inflammation in MS, but scientists need to conduct more carefully designed studies.

The researchers, led by Egil Røsjø of Akershus University Hospital, Lørenskog, Norway, wanted to see if inflammation could be blocked by vitamin D in RRMS. They gave high-dose oral vitamin D3 to 68 people with RRMS and measured inflammation using eleven standard markers. They also measured the amount of active vitamin D that was present in the body, at the beginning of the study and at the 96th week of the study.

Blood levels of vitamin D rose in people taking the supplements, but there were no changes in inflammation markers in people with MS taking the supplement when compared to the ones who did not take the supplement (the placebo group). Changes in inflammation were only measured in people who were taking specific medications to block inflammation. These people had significantly higher levels of the anti-inflammation markers known as interleukin-1 receptor antagonist and chemokine (C-X-C motif) ligand 16.

In their study report, the researchers noted “We conclude that in this study of RRMS patients, high-dose oral vitamin D3 supplementation prominently increased serum 25(OH)D levels without affecting markers of systemic inflammation, while a more anti-inflammatory phenotype was found among patients on immunomodulatory treatment.”

The current study does not support a role of vitamin D in blocking inflammation in RRMS. Vitamin D may, however, have other beneficial effects in people with MS which need to be further examined.

Notably, a recent study of sunlight exposure, a source of vitamin D, also failed to support a beneficial effect of vitamin D in MS. Exposure to sunlight was associated with an increase in age at which people were diagnosed with MS by a small amount. In the study however, scientists did not find any association between using vitamin D or other supplements and the delay of MS onset. The impact of vitamin D on MS requires further study before it can be concluded that it has a beneficial effect on the disease.