Possible Causes of MS

Researchers have studied a variety of possible causes for multiple sclerosis (MS), and a combination of factors appears to be involved. A popular theory looks at commonly known slow-acting viruses (one that could remain dormant for many years), such as measles, herpes, human T-cell lymphoma, and Epstein-Barr. After being exposed to one of these viruses, some researchers theorize that MS may develop in genetically susceptible people. While research is ongoing, no specific genes for MS have been identified. Genes have some role in susceptibility to MS, but the exact mechanisms remain unclear.

Some scientists are looking for a connection between MS and nutritional factors, including fat intake, as well as deficiencies in fish oil and Vitamin D. The idea that a diet rich in saturated fat may increase one’s risk of getting MS, as well as worsen their disease course, has been a popular theory for several decades. In addition to food and supplements, Vitamin D is also derived from sunlight. Reduced sunlight may be involved in the development of MS.

As noted earlier, populations living closer to the equator have a lower incidence of MS. A popular theory is that those living closer to the equator are exposed to more sunlight and therefore are less likely to experience a Vitamin D deficiency. Studies suggest that low levels of Vitamin D may increase one’s risk of MS.

Recent studies with high levels of Vitamin D supplementation, however, have not seen any therapeutic effects on disease progression or relapses. But interestingly, some of these studies have seen a reduction in new lesions, as viewed on magnetic resonance imaging (MRI). Additionally, Vitamin D is also being studied with certain symptoms of MS, including fatigue.

Individuals looking to take Vitamin D supplements as part of their treatment regimen should consult their physician. Continued high-dose Vitamin D supplementation can lead to life-threatening conditions, including kidney failure and heart arrythmias.

Parasites, which can modulate the immune system and dampen its responses, are a possible risk-reduction factor in the development of MS. The parasites in this instance are “helminths,” which refer to a wide variety of worms. People who have parasites are less likely to be diagnosed with MS, and since parasites are less common in the United States, the lack of parasites may contribute to the higher incidence of MS in this country. However, some types of worms could possibly make MS worse, so more research is needed.

In recent years, researchers have found that interactions between a person’s microbiome and their immune cells may contribute to the development and severity of many disease states – including MS. The microbiome refers to the many millions of bacteria that reside in a person’s body, with current research focusing mainly on the bacteria that live in the intestines (referred to as “gut microbiota”). Specifically, researchers have hypothesized that imbalances in the number or types of different strains of bacteria could potentially cause the immune system to be inappropriately activated to develop an autoimmune disease. Multiple groups are currently conducting research on the microbiome and its potential connection with MS.

Another factor linked to MS is cigarette smoking. One study shows that women who smoke are 1.6 times more likely to develop MS than women who are non-smokers. Individuals with MS who smoke also appear to be at a much greater risk of experiencing a more rapid progression of their disease.

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