The Role of Vitamin D in Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune inflammatory disease in which the fatty myelin sheaths around the axons of the brain and spinal cord are damaged, leading to demyelination and scarring. There is a broad range of symptoms including: loss of sensitivity, tingling, numbness, muscle weakness, muscle spasms, difficulty moving, impaired coordination, lack of balance, problems in speech or swallowing, visual problems, fatigue, acute or chronic pain, bladder and bowel difficulties. Cognitive impairment and emotional symptoms of depression or unstable mood are also common.[1] Symptoms of MS usually appear in episodic acute periods of worsening (called relapses, attacks, or "flare-ups"), in a gradually progressive deterioration of neurological function.[2] Symptoms vary, because the location and severity of each attack can be different, lasting for days, weeks or months. These episodes alternate with periods of reduced or no symptoms (remissions). Disease onset usually occurs in young adults, and it is more common in women.[1] 

Does vitamin D help MS?

Research suggests that there may be a link between vitamin D and MS. Low levels of vitamin D have been linked to increased risk and activity of a variety of autoimmune conditions including multiple sclerosis, rheumatoid arthritis, diabetes mellitus and inflammatory bowel disease. Studies have shown that vitamin D deficiency and insufficiency is prevalent among those with multiple sclerosis.[3,4]

The link between vitamin D and multiple sclerosis was first proposed after it was observed that there are increasing incidences of MS the farther away you get from the equator.[5] Vitamin D is naturally produced in the body when the skin is exposed to the sun's light, specifically rays in the ultraviolet B (UVB) light spectrum. Rates of MS relapse also increases in the winter, when there is less sun and people tend to have lower levels of vitamin D.[6] This pattern of increasing MS cases with increasing latitude and the winter season suggests that exposure to UVB may offer protection from MS. 

The National MS Society was founded in 1946 and strives to stop MS in its tracks and end MS forever. They provide a wealth of knowledge about the disease and are a critical funding source for many multiple sclerosis studies, including research on MS and vitamin D. One National MS Society funded study involving more than 7 million US military personnel found that higher circulating levels of vitamin D were associated with a lower risk of multiple sclerosis.[7] 

Another study of more than 187,000 women looking at the relationship between vitamin D intake and incidence of multiple sclerosis found that women with higher dietary intake of vitamin D had a 33% reduced risk of developing MS compared to those with lower intake, and women who took vitamin D supplements had a 41% reduced risk of developing MS compared to those who did not take supplements.[8] 

Some studies have suggested that vitamin D could help manage autoimmune conditions like MS due to the role vitamin D plays in regulating immune and inflammatory responses in the body. Vitamin D has been shown to modulate the activation of regulatory T-cells for supporting immune system activity, while also preventing the overactive response characteristic of autoimmune diseases.[9]

A study done by researchers out of Harvard’s School of Public Health found that having low vitamin D levels early in the disease course are a strong risk factor for increased long-term MS activity and progression.[18] Multiple studies have found a significant correlation between lower levels of vitamin D and increased MS severity as measured by EDSS (Expanded Disability Status Scale) score.[19,20] EDSS score is a measure of MS disease severity and takes into account data from a neurological examination and the patient's ability to walk.  

In a randomized, double-blind, placebo-controlled trial, patients given vitamin D3 as an add-on to their MS treatment experienced a decrease in the number of brain lesions and a marginal decrease in disability accumulation.[21] In a 5‐year longitudinal MS cohort study, researchers examined the correlation between vitamin D status and brain lesions and found that higher vitamin D blood levels were associated with lower brain lesion activity.[22] All of these studies support the idea that vitamin D can help manage symptoms of MS, reduced disease severity, and reduce number of relapses.

Can vitamin D deficiency mimic MS?

Vitamin D deficiency and MS both have a wide range of symptoms, some of which overlap between the two conditions.  Having a deficiency in vitamin D can cause joint and bone pain, bone loss, weakening of the bones, and numbness. Vitamin D deficiency can also cause muscle pain and weakness, getting sick often, fatigue, and a decline in mental health.  

Among other symptoms, multiple sclerosis can lead to numbness, muscle weakness, muscle spasms, fatigue, cognitive impairment and emotional symptoms of depression or unstable mood. These are all symptoms that can be associated with vitamin D deficiency as well. If you are suffering from any of the above symptoms please see a doctor to get a diagnosis and establish a treatment plan. 

How does vitamin D affect pregnancy of patients with MS?

Studies indicate that higher maternal vitamin D levels can decrease risk of multiple sclerosis in offspring.[23,24] A study that looked at the vitamin D level of mothers during pregnancy found that MS risk was 90% higher in the children of vitamin D deficient mothers compared to children whose mothers were not deficient.[25] 

 Another study that looked at the neo-natal vitamin D level of 521 MS patients and 972 controls using data from the nationwide Danish MS Registry and Danish Newborn Screening Biobank, found that those in the highest risk group for MS had the lowest vitamin D levels and those in the lowest risk group for MS had the highest vitamin D levels.[26] These findings show that during pregnancy, having a vitamin D deficiency may increase multiple sclerosis risk of offspring. 

Can vitamin D reverse MS?

While vitamin D cannot cure MS, studies have shown that increasing vitamin D level can help slow progression of the disease. Some studies have also suggested that vitamin D may help prevent MS relapse and reduce the severity of flare-ups. 

Since it is common for MS patients to have low levels of vitamin D, and higher levels of vitamin D have been tied to better MS outcomes, it is important that those with MS take steps to maintain a sufficient vitamin D level. Restoring vitamin D levels to a healthy range has been shown to help patients with autoimmune diseases.[27]   

How much vitamin D should MS patients take?

Among the medical community, there is debate on the best way to get vitamin D. Some doctors recommend oral supplements, but there are a variety of reasons why vitamin D pills may not be the best option. Oral vitamin D supplements are not effective for a surprisingly large number of people, and don’t provide the same health benefit as exposure to light. To learn more about this topic, click here to read our article about why vitamin D pills fall short. 

More research is needed to determine the best form of vitamin D for MS and a recommended vitamin D protocol for the management of multiple sclerosis. Vitamin D dosage recommendations vary greatly among the medical community.  

The Institute of Medicine’s (IOM) recommended dietary allowance for vitamin D is 600 International Units (IU) per day. This recommendation is based on what is needed to prevent rickets and osteoporosis, not what is needed to impact incidences or severity of MS. Many vitamin D researchers disagree with this recommendation and say that the IOM’s recommended allowance isn’t enough to prevent deficiency or support bone health. Generally, 4,000 IU or less per day is considered safe, as long as your blood values are being monitored. It is important to avoid excessive doses of oral vitamin D. If vitamin D intake is too high, it can cause elevated blood calcium levels and potentially dangerous consequences.

Obtaining vitamin D from light allows your body to self-regulate vitamin D production and make as much as it needs to stay healthy, without any risk of overdose or toxicity. Unlike with oral supplements, you cannot overdose on vitamin D3 produced by your skin. If you have enough vitamin D, your body will simply produce less.