4 Possible Causes of Multiple Sclerosis
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4 Possible Causes of MS

Multiple Sclerosis (MS)


  1. Multiple sclerosis (MS) is a progressive, neurological disease that can affect the central nervous system (CNS).
  2. The exact cause of MS is unknown. However, scientists believe that four factors may play a role in development of the disease.
  3. Immunologic, genetic, environmental, and viral causes are all considered to play a factor in MS.

Multiple sclerosis (MS) is a progressive neurological disease that can affect the central nervous system (CNS). Millions of nerve cells in the brain send signals throughout the body to control movement, sensation, memory, cognition, and speech. Every time you take a step, blink, or move your arm, your CNS is at work.

Nerve cells communicate by sending electrical signals via nerve fibers. A layer called the myelin sheath covers and protects these fibers. It ensures that each nerve cell properly reaches its intended target.

Immune cells mistakenly attack and damage the myelin sheath in people with MS. This damage results in the disruption of nerve signals.

What Causes MS?

Damaged nerve signals can cause debilitating symptoms, including:

  • walking and coordination problems
  • muscle weakness
  • fatigue
  • vision problems

MS affects everyone differently. The severity of the disease and the types of symptoms vary from person to person. The exact cause of MS is unknown. However, scientists believe that four factors may play a role in the development of the disease.

Cause 1: Immunologic

MS is considered an immune-mediated disease. That is, the immune system malfunctions and attacks the CNS. Researchers know that the myelin sheath is directly affected, but they don’t know what triggers the immune system to attack the myelin.

Research about which immune cells are responsible for the attack is ongoing. Scientists are seeking to uncover what causes these cells to attack. They’re also searching for methods to control or stop the progression of the disease.

Cause 2: Genetic

Several genes are believed to play a role in MS. Your chance of developing MS is slightly higher if a close relative, such as a parent or sibling, has the disease.

According to the Multiple Sclerosis Foundation, if one parent has MS, the risk of their children getting the disease is estimated to be between 2 and 5 percent.

Scientists believe that people with MS are born with a genetic susceptibility to react to certain (unknown) environmental agents. An autoimmune response is triggered when they encounter these agents.

Cause 3: Environmental

Epidemiologists have seen an increased pattern of MS cases in countries located farthest from the equator. This correlation causes some to believe that vitamin D may play a role.

Vitamin D benefits the function of the immune system. People who live near the equator are exposed to more sunlight. As a result, their bodies produce more vitamin D.

The longer your skin is exposed to sunlight, the more your body naturally produces the vitamin. Since MS is considered an immune-mediated disease, vitamin D and sunlight exposure may be linked.

Cause 4: Infections

Researchers are considering the possibility that viruses and bacteria may cause MS. Viruses are known to cause inflammation and a breakdown of myelin (called demyelination). Therefore, it’s possible that a virus could trigger MS.

Several viruses and bacteria are being investigated to determine if they’re involved in the development of MS. These include:

  • measles virus
  • human herpes virus-6 (HHV-6)
  • Epstein-Barr virus (EBV)

Other Risk Factors

In addition to genetics, the environment, infections, and the immune system, other risk factors may increase your chances of developing MS. For example:

  • Sex: Women are two to three times more likely to develop MS than men are.
  • Age: According to the Mayo Clinic, MS usually strikes between the ages of 20 and 40.
  • Ethnicity: People of northern European descent are at highest risk of developing MS.

What Can Trigger MS Symptoms?

There are several triggers that people with MS should avoid. These include:


Stress can trigger and worsen MS symptoms. Practices that help reduce and cope with stress can be helpful for people with MS. Add destressing rituals to your day, such as yoga or meditation.


Cigarette smoke can add to the progression of MS. If you’re a smoker, look into effective methods of quitting. Avoid being around secondhand smoke.


Not everyone sees a difference in symptoms due to heat, but avoid direct sun or hot tubs if you find you react to them.


There are several ways that medication can worsen symptoms. If you are taking many drugs and they interact poorly, talk to your doctor about which drugs are vital and which ones you may be able to stop.

Some people stop taking their MS medicines because they have too many side effects or they believe they are not effective. However, these medicines are critical to help prevent relapses and new lesions, so it’s important to stay on them.

Lack of Sleep

Fatigue is a common symptom of MS. If you’re not getting enough sleep, this can decrease your energy even more.


From urinary tract infections to the cold or flu, infections can cause your symptoms to worsen. In fact, infections cause approximately one-third of all flare-ups of MS symptoms, according to the Cleveland Clinic.

Treatment for MS

Although there is no cure for MS, there are treatment options to help manage MS symptoms.

The most common treatment category is corticosteroids, such as oral prednisone and intravenous methylprednisolone, which reduce nerve inflammation. In cases that don’t respond to steroids, some doctors prescribe plasma exchange. In this treatment, the liquid portion of your blood (plasma) is removed and separated from your blood cells, which are then mixed with a protein solution (albumin) and put back into your body.

There are currently no therapies proven to slow the progression of primary-progressive MS. For relapsing-remitting MS, several disease-modifying therapies are available but they all entail significant health risks. Talk to your doctor about whether any are right for you.


While much of what causes and prevents MS is a mystery, what is known is that those with MS are living increasingly full lives due to treatment options and overall improvements in lifestyle and health choices. With continued research, strides are being made every day to help stop the advance of MS.