7 Surprising Facts About Multiple Sclerosis

Multiple sclerosis (MS) is the most common progressive neurologic disease in young adults worldwide. In the United States, roughly 300,000–400,000 American adults have MS.

MS is an autoimmune disease. Autoimmune diseases occur when the immune system mistakenly attacks healthy cells, leading to damage in the affected area of the body. In MS, the attack is on the brain and spinal cord, leading to symptoms such as fatigue, pain, cognitive and mood changes, and bladder or bowel dysfunction.

Below are some interesting facts about MS that you might not know.

Fast Facts About Multiple Sclerosis - Illustration by Zoe Hansen

Verywell / Zoe Hansen

An "Invisible Illness"

Invisible illnesses (also called silent conditions and disabilities) cannot be seen by other people at first glance. People with an invisible illness may not appear sick even though they have symptoms of a chronic illness. These symptoms can even be debilitating.

MS can be considered an invisible illness. The symptoms of the disease can significantly affect a person's day-to-day life, but this impact might not be immediately apparent to others.

According to the National Multiple Sclerosis Society, having symptoms that are not easily seen by others can have a negative impact on a person's confidence and their relationships. It can also discourage people from asking for help when they need it or from seeking treatment.

Coping With Invisible Illness

When dealing with an invisible illness such as MS, it's important to find a good support system. This includes communicating with the people in your life and asking for help when you need it.

More Common in Colder Climates

Geography is an environmental factor that contributes to the development and progression of MS. A 2012 review published in the International Journal of Molecular Sciences looked at different parts of the world that have a higher prevalence of MS and tried to determine what these places have in common.

The study found that people living in higher latitudes—or areas of the world that are farther from the equator—have higher rates of MS than people living in other parts of the world. Examples of the places identified as having a higher prevalence of MS are Finland and Scandinavia.

Vitamin D May Help

Vitamin D plays a role in the health of the immune system. It's thought that being deficient in the nutrient can increase the risk of developing MS. Vitamin D level changes can also affect the activity of the disease, which means that low vitamin D levels can both increase the risk of developing MS and affect how the disease progresses.  

Studies have investigated whether getting more vitamin D through either natural means (the sun) or supplementation could help people with MS. A study from 2018 found that people with MS at risk for vitamin D deficiency could benefit from taking supplements of the nutrient.

However, more research is needed to determine how much benefit there could be to taking vitamin D if you have MS. The main conclusion drawn from the studies is that people with MS should try to avoid becoming deficient in vitamin D.

The Cause Is a Mystery 

The cause of MS, like many other autoimmune diseases, is not known. Medical researchers have yet to figure out exactly why the immune system mistakes healthy cells for dangerous ones and attacks them.

Even though some triggers of MS have been identified, the reason MS develops and progresses is not well understood.

Genetics is considered a risk factor for MS. Research has identified other possible contributors to the onset of MS, including vitamin D deficiency, the season in which a person is born, viral infections such as Epstein-Barr, and smoking tobacco.

Pregnancy May Ease Symptoms 

According to the National Multiple Sclerosis Society, when a person with MS becomes pregnant, their symptoms may decrease. Changes in the body that take place during the second and third trimester of pregnancy can lead to less overall inflammation, which may help ease a person's symptoms and even lead to fewer flare-ups.

It's been thought that MS symptoms will flare up right after pregnancy. However, recent research has shown that this may not be true. MS flare-ups ebb and flow sporadically, and there is no evidence that a person is more likely to have a flare-up postpartum than at any other time over the course of their disease.  

Managing MS Flare-Ups During Pregnancy

If you have a flare-up of MS symptoms while you are pregnant, it's important to talk to your provider.

While most MS medications are not safe to use during pregnancy, you do have options for treating your symptoms during this time.

It's More Common in Women

Any person can have MS, but women are four times more likely to develop the condition than men. Research has suggested that differences in the brains of men and women may affect their risk for MS.

One study in 2014 looked at levels of a type of blood vessel receptor protein known as S1PR2 and found that women had higher levels of the specific protein than men. The protein was also found in higher amounts in the areas of the brain that are damaged by MS.

The reason that this specific receptor protein was of interest to researchers is that it decides how many immune cells (which help the body ward of infection and disease) can cross through blood vessels and go into the brain. When the immune cells get into the brain, they cause inflammation, which in turn leads to the development of MS.

1 in 5 New Patients Are Misdiagnosed 

It's quite common for MS to be misdiagnosed. Roughly 18% of MS cases are eventually classified as misdiagnoses. Typically, MS is diagnosed using the McDonald criteria, a set of diagnostic criteria designed to determine whether a person is exhibiting the telltale signs of the disease.


5 Myths About Life With MS

MS can be hard to diagnose because it has nonspecific symptoms that do not necessarily appear the same way in every person with the condition. For example, it's typical for MS patients to have discreet neurological symptoms that come on quickly, go away (resolve), then come back again months or years later.


The fickle nature of the disease and its symptoms make MS a difficult disease to diagnose.

A Word From Verywell

There is a lot that we still do not understand about multiple sclerosis. We do know that certain factors can contribute to disease development and that there are some effective ways to treat it. In some cases, the progression of the disease can be slowed and people can effectively manage their symptoms.

Frequently Asked Questions

  • How does MS affect the body?

    MS can affect the body in many ways, but it depends on the person and how severe their symptoms are. MS tends to cause problems with mobility, cognitive function, sexual function, bladder and bowel control, and vision changes. The progression of the disease and which nerves are damaged will also determine how a person's body is affected.

  • Is MS contagious?

    MS is not contagious. If you have MS, you cannot give it to someone else. It is also not directly inherited, but there may be a genetic component to a person's risk of developing the disease.

  • Can MS be cured?

    There is no cure for MS, but it is not considered to be a fatal disease. According to the National Multiple Sclerosis Society, the lifespan of a person with MS is not directly affected by the disease but, rather, its complications. That said, many of the complications of MS—such as heart disease—can be prevented or managed effectively.

    People with MS have a minimal decrease in their life expectancy (roughly seven years) compared to people in the general population.

  • What are the very first signs of MS?

    When the first attack of MS symptoms occurs, people may experience blurry vision, eye pain, numbness or tingling in their legs or face, or a feeling as though an electric shock is moving through their head or neck.

    The first attack of MS symptoms is called clinically isolated syndrome (CIS). MS is only diagnosed after a subsequent attack of symptoms. Some people have CIS and never develop MS.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Angelica Bottaro
Angelica Bottaro is a professional freelance writer with over 5 years of experience. She has been educated in both psychology and journalism, and her dual education has given her the research and writing skills needed to deliver sound and engaging content in the health space.