News Room

The Sun's production of Vitamin D affects MS progression

The Connection between MS And Vitamin D

Did you know that you can help prevent progression of multiple sclerosis by being in the sun more? Your body produces Vitamin D when sunlight hits the skin. Sun exposure is the most important natural source of Vitamin D. (To a lesser extent, Vitamin D is found in foods.) The good news about Vitamin D:  several studies have shown that increasing the level of Vitamin D both lowers the risk for developing MS, and, for those managing the disease, slows its progression.

While the cause of MS is unknown, a combination of genetics and environmental factors appears to be responsible for its onset. There are credible theories that exposure to the Epstein-Barr virus (EBV), smoking, and gut microbiomes can increase the chance of developing MS.  What has been shown conclusively is that low Vitamin D levels affect the course of the disease.

The benefits of increasing Vitamin D levels apply to other autoimmune disorders, such as lupus, psoriasis, and Crohn’s disease. The impact of Vitamin D on the immune system is to reduce the activity of T-cells which drive autoimmune diseases. For MS, T-cells attack the nervous system and cause damage to myelin, nerve fibers, and the cells that make myelin.

The Geographical Distribution of MS


Looking at MS through the lens of sun exposure leads to a geographic analysis.

MS is generally most prevalent in northern geographic latitudes. The highest rates of MS are generally found between the latitudes of 45 degrees north and 65 degrees north. This same latitudinal prevalence rate can be found in similar latitudes in the southern hemisphere. The disease is very rare near the equator. (Source)

The map of the U.S. below delineates regional differences in MS prevalence. As the map shows, MS’ prevalence in the northern regions of the U.S. — Northeast and Midwest – is statistically significantly higher than in the southern and western regions.

U.S. map showing prevalence of MS by region and by gendre

Vitamin D Supplements: Consult with your Physician


The connection of geography with Vitamin D levels and the impact on MS is a newer revelation. As latitude increases, the amount of Vitamin D UV, i.e., sun exposure, decreases dramatically, inhibiting Vitamin D synthesis in humans. Vitamin D supplementation is considered an important modifiable environmental risk factor for development of multiple sclerosis, and an important addition to a medication regimen to prevent its progression.

Most doctors will check the blood levels of Vitamin D in their MS patients, and if the levels are low, recommend supplementation. There is some debate over how much Vitamin D supplementation is enough…and how much is too much?

Recommended Vitamin D Doses


Most doctors will recommend a daily intake of 400 to 600 international units (IUs) of vitamin D for patients with low Vitamin D levels. If you are diagnosed with vitamin D deficiency, some believe it may be appropriate to use up to 50,000 IUs weekly for up to three months, until vitamin D levels become normal. Once normal, a maintenance dose is recommended. The maintenance dose often ranges between 2,000 and 5,000 IU daily.

Some caution that more Vitamin D is not always better. Too much Vitamin D can be toxic. Signs and symptoms of excessive Vitamin D include nausea, vomiting, constipation, poor appetite, weakness, and weight loss as well as kidney stones. Source

If you have MS or have family members with MS, talk to your doctor about checking your blood levels of Vitamin D and discuss if Vitamin D supplementation might be a good idea for you.

Leave a Comment

Your email address will not be published. Required fields are marked *