Vitamin D provides the body with many benefits, from promoting calcium absorption, which encourages bone health, to lowering blood pressure. Research has also shown it can benefit the immune system. Building on that, new research published in the journal Neurology finds high doses of it may also help people with multiple sclerosis (MS), a debilitating disorder in which a person’s own immune system destroys their nerve cells’ protective covering.

"These results are exciting, as vitamin D has the potential to be an inexpensive, safe, and convenient treatment for people with MS," said study author Dr. Peter A. Calabresi, of Johns Hopkins University School of Medicine in Maryland, in a press release .

For the study, the researchers looked at 40 people with Relapsing-Remitting MS (RRMS), the most common form of MS. People who suffer from this type of MS experience short, repeated periods of flare-ups, during which new symptoms, like fatigue, double vision, and difficulty walking can appear.

Split into two groups, the participants received either 10,400 IU or 800 IU of vitamin D3 supplements — 600 IU is the recommended daily allowance — for six months. Each participant also had their blood tested at three- and six-month follow-ups to see how their immune systems T cells (the fighters) responded to the Vitamin D. The researchers found that patients who took the higher doses of vitamin D experienced a reduction in T cells associated with MS nerve damage, while those who took a lower dose experienced nothing.

While there is no cure for MS, there are treatments that can help slow its progression and reduce the severity of symptoms. Among these are corticosteroids, which reduce nerve inflammation, and plasma exchange, a procedure in which plasma is removed from the blood and mixed with the protein albumin before being put back into the body. Albumin helps restore homeostasis to blood plasma, where destructive T cells reside.  

Beyond these, just this year, researchers from the Walter and Eliza Hall Institute developed a drug-like molecule capable of halting inflammation tied to the disease’s progression. This research, however, is still in its preclinical stages. And it’s possible that high-dose vitamin D supplementation may move forward faster if future research finds it definitively works, Calabresi said. "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.”

Source: Sotirchos E, Bhargava P, Eckstein C. Safety and immunologic effects of high- vs low-dose cholecalciferol in multiple sclerosis. Neurology. 2015.