Did you know that there are trillions of teeny living things inside you?

Most of them are found in your digestive system. This is your gut microbiome. There are more of these microbes than cells in your body. It may sound alarming, but it’s totally normal.

These bacteria, fungi, and other organisms play a variety of roles. They help us use and digest our food. They also appear to be connected with our immunity, overall health, and risk of disease.

By exploring our gut microbes, researchers want to understand how they are linked to our overall health.

The microbiomes of people living with multiple sclerosis (MS) are different from those of people without MS. Based on this information, the hope is that new therapies can be developed to help people with MS.

Your gut microbiome is all of the colonies of microscopic living things in your digestive system. There are more than 1,300 types of bacteria living in the gut and even more when specific strains are counted.

No two people have exactly the same gut microbiome, but there are patterns based on a variety of factors:

  • how you were delivered (cesarean or vaginal delivery)
  • how you were fed as an infant (breastfed or formula)
  • genetics
  • age
  • medications
  • antibiotic use
  • stress
  • where you live in the world
  • diet

Our health and our gut microbiome are tightly linked. What isn’t well understood is what happens first.

Does the microbiome change, setting us up for disease? Or does a change in health create a shift in your microbiome? Researchers are still exploring these big questions.

The rates of autoimmune disease and allergies have gone up in recent years. One theory to explain this is the hygiene hypothesis.

Many of us live in clean environments with little exposure to pathogens. However, with less infectious disease, we see more cases of allergies and autoimmune disease. The theory is that this rise is caused by major changes in the gut microbiome due to reduced exposure.

When any of the colonies in your gut microbiome are out of balance, it’s known as dysbiosis. Dysbiosis can cause a variety of digestive symptoms. It’s associated with the development of many autoimmune diseases.

Normally, the bacteria in our digestive tract do not enter the rest of our body. There is a strong barrier wall of cells around the digestive tract. This prevents bacteria in the digestive tract from “leaking” into the bloodstream.

Dysbiosis in the digestive tract can cause gaps in these barrier walls. Bacteria that normally stay in the digestive tract can get out, causing inflammation. This inflammation is linked with autoimmune diseases, including MS.

Several studies have compared the gut microbiomes of people with and without MS. There are distinct differences. It’s still unclear if the microbiome increases the risk of MS flares or if MS flares change the gut microbiome. It may be a combination of both.

Several studies have shown that people with MS have gut dysbiosis. Certain gut bacteria create more inflammation in the body and this is seen in some people with MS. In mouse studies, some MS-like symptoms are improved by changing the gut microbiome.

Those with MS have less Prevotella histicola bacteria in their gut compared to those without MS. Copaxone (glatiramer acetate), a disease-modifying therapy, can cause these bacteria colonies to increase.

One study showed similar benefits in mice given Prevotella histicola compared to mice given Copaxone. It’s not yet known if this will work in humans.

Some factors, like genetics and environment, are out of your control. Our gut microbiome is established early on in life, but there are factors that affect it.

Some changes promote greater health and diversity in our microbiome. Other changes can harm.

Here are some things you can do to promote a healthy, balanced gut microbiome:

  • Eat more fiber. Fiber provides food for all those little bacteria in your gut. Fiber comes from fruits, vegetables, beans, lentils, nuts, seeds, and whole grains.
  • Reduce alcohol intake. Alcohol is shown to contribute to dysbiosis. If you drink, you may want to consider cutting down.
  • Eat fermented foods. Fermented foods are sources of healthy bacteria and may provide health benefits. Fermented foods include kimchi, tempeh, yogurt, kefir, miso, and sauerkraut.
  • Manage stress. Stress can affect the health of your gut microbiota. Try out some stress-relieving techniques, such as yoga or meditation, to cope with stress.
  • Use antibiotics wisely. Along with the bad bacteria, antibiotics can also destroy some of the good ones. This can lead to dysbiosis. It’s important to only use antibiotics when needed and take them as directed. Taking a probiotic supplement may restore some of the good bacteria.
  • Explore probiotic supplements. Probiotic supplements may be helpful. More research is needed to figure out the best dose and strain for specific conditions. The US Probiotic Guide could be a good place to start.

Trillions of microbes live in and on the human body. Most of these are in the gut.

There is interest in how the types of bacteria in our gut can influence our health.

A person with MS is more likely to have dysbiosis. Dysbiosis is when the gut microbiome is out of balance. This increases the risk of autoimmune diseases and inflammation.

Eating a high-fiber diet with fermented foods can support a healthy gut microbiome.

Research is ongoing to see how changing the gut microbiome may help people with MS.