What causes multiple sclerosis (MS)?

Dr. Jeanne Morrison, PhD
Family Practitioner

The cause of multiple sclerosis is unknown, although many believe it to be an autoimmune disease. An autoimmune disease is one in which the body attacks itself. For some unclear reason, the body begins damaging the myelin sheath, the protective layer of tissue around the nerves. The exposed nerves have a harder time sending messages through the body.

Dr. Michael T. Murray, ND
Naturopathic Medicine Specialist

The cause of multiple sclerosis (MS) remains to be identified conclusively. It is thought that MS is an autoimmune disease, that is, a disease where the immune system attacks body tissues as if they were foreign proteins. What triggers this process in initiating or exacerbating MS is unknown.

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From the bestselling authors of The Encyclopedia of Natural Medicine, the most comprehensive and practical guide available to the nutritional benefits and medicinal properties of virtually everything...
Donna Hill Howes, RN
Family Practitioner

Scientists have learned a great deal about multiple sclerosis (MS) in recent years; still, its cause remains elusive. Many investigators believe MS to be an autoimmune disease—one in which the body, through its immune system, launches a defensive attack against its own tissues. In the case of MS, it is the nerve-insulating myelin that comes under assault. Such assaults may be linked to an unknown environmental trigger, perhaps a virus.

This answer from the National Institute of Neurological Disorders and Stroke.

Brooke Randolph
Marriage & Family Therapy Specialist

Although there have been some positive evidence of symptom episode reduction from recent treatment medications, researchers do not seem to have a solid understanding of the origins of multiple sclerosis (MS). Genetics, environmental factors, and exposure to infectious disease are all considered possible causes and/or contributors to multiple sclerosis.

Although the root cause of multiple sclerosis (MS) is unknown, much has been learned:

  • The immune system causes much of the damage from MS.
  • It periodically attacks the brain, causing the damage that leads to MS.

What is not known is why the immune system causes this attack on the brain.

The cause of multiple sclerosis (MS) is unknown, but most researchers think it results from an abnormal response by the body's immune system. Some researchers believe this abnormal immune response could be caused by a virus, although it is unlikely that there is just one virus responsible for triggering the condition. Researchers do know that MS is not contagious. And while it is not an inherited disease, genetic susceptibility plays a role. There is a higher risk for MS in families where it has already occurred. Other possible triggers include environmental exposures to toxins and heavy metals, as well as low levels of vitamin D. Smoking and obesity may worsen the condition.

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Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

No one knows exactly why people get multiple sclerosis (MS). It is not contagious, and while it isn’t directly inherited, those who have family members with MS are more likely to get MS themselves. However, research has assessed certain factors that may influence one’s risk of developing MS:

  • Virus infections: Various studies have connected many viruses with an increased risk of developing MS. One virus in particular is the Epstein-Barr virus (EBV), which causes mononucleosis.
  • Genetics: While the average person has about a one in 750 chance of developing MS, someone who has a parent or sibling with MS has a one in 40 chance of developing MS. However, the connection isn’t clear, and doctors do know that one doesn’t develop MS because of genetics alone.
  • Birth month: One study found that those born in May were more likely to develop MS, and those who were born in November were less likely to develop MS.
  • Smoking: Those who smoke have a higher risk of developing MS.
  • Sunlight and vitamin D: Multiple studies have suggested that those who get less sunlight are at higher risk of developing MS. For example, those who live in northern areas that get less sunlight are more likely to develop MS. This may be connected to levels of vitamin D. Another study found that women who took at least 400 IUs (international units) of vitamin D a day had a significantly lower risk for MS.

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Dr. Louis Rosner

No one knows what actually causes multiple sclerosis (MS), but we do know that it is an acquired disease—you are not born with it. Multiple sclerosis is also an exogenous disease, meaning that it is contracted from the outside. And fortunately, it is not contagious. American researchers have shown that the rate of increased prevalence among husbands and wives is only 1 percent. In England, the prevalence of MS among husbands and wives is less than among the general population, occurring at a rate of 4.9 per 10,000 compared with 5.0 per 10,000.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.