Individuals with a higher intake of vitamin D and higher vitamin D blood levels are less likely to develop MS1, according to a 2018 review from Neurology and Therapy. Specifically, women that consumed approximately 700 IU of vitamin D daily had a 33% lower incidence of MS compared to those who consumed less vitamin D per day.

To put this amount into perspective, 93%2 to 100% of the U.S. population is failing to consume even 400 IU per day. Evidence suggests that 5,000 IU of vitamin D3 daily is the average amount needed to help folks reach and maintain truly optimal vitamin D status [i.e., 25(OH)D serum levels of 50 ng/ml or higher]. 

Research suggests vitamin D deficiency is also extremely prevalent in multiple sclerosis populations—one small study of 149 MS patients published in the EPMA Journal in 2019 found that 90% were vitamin D deficient3. This is significantly higher than the U.S. adult population (of which 29% are deficient in vitamin D4).

While clinical sufficiency is defined as 30 ng/ml or higher, endocrinologists and other leading wellness experts suggest that 50 ng/ml is the cutoff for true sufficiency—and research on disease prevention suggests a higher 25(OH)D level is far more beneficial for lowering disease risk, including MS. In fact, a JAMA study evaluating over seven million U.S. military personnel found that individuals with vitamin D levels greater than 40 ng/ml were 62% less likely5 to develop multiple sclerosis.

The science is clear: Vitamin D deficiency is extremely prevalent in MS patients; maintaining healthy vitamin D status can help reduce your risk of developing MS.