What Does Research Show About the Importance of Our Gut Microbiome

What Is Your Gut Microbiome?

Your gut is another way of saying your gastrointestinal (GI) system or your digestive system. It includes your stomach, small and large intestines, and colon. Your gut microbiome includes all of the microorganisms that naturally live inside of your gut.

Each person has a completely unique gut microbiome that includes trillions of microorganisms, including many different species of:

Research so far has mostly focused on the bacteria present in your gut. Although viruses, fungi, and parasites also have important functions, we know the most about what the bacteria in your gut do. Bacteroidetes and Firmicutes species are often the focus of research.

The first organisms in your gut microbiome are those you inherit from your birth mother during vaginal birth or breastfeeding. Your gut microbiome continues to develop as you’re exposed to new microorganisms in your diet and environment.

Most of the microorganisms found in your gut are beneficial to you. However, a small number are pathogenic — harmful microbes that cause disease. Everyone has some pathogenic microbes. When you’re healthy, the helpful and pathogenic microbes coexist in a balance that doesn’t cause any problems. If the balance is disturbed for any reason, it can throw off the balance between helpful and harmful microbes and cause problems. We’ll talk about what factors can disturb this balance later in this article.

What Does Your Gut Microbiome Do?

Some health experts describe the gut microbiome as an invisible organ. Your gut microbiome has many functions in several different body systems.

Nervous System

Your nervous system is the part of your body that helps you think, move, and feel. It consists of your brain, spinal cord, and nerves.

The microbiomes in your gut play an important part in the gut–brain axis — a two-way communication between your digestive system and your brain. Bacteria can encourage your body to make certain neurotransmitters (chemical signals your brain uses to communicate) and other chemicals that are released into your bloodstream and travel to your brain.

Researchers have learned that the microbes in your gut play an important role in disorders of gut–brain interaction, previously known as functional gastrointestinal disorders. One example of a disorder of gut–brain interaction is irritable bowel syndrome (IBS), which affects up to 15% of people in the United States (US).

What Factors Can Affect Your Gut Microbiome?

When the balance of your gut microbiome is disrupted, it’s called dysbiosis. You may have dysbiosis if you have too few beneficial bacteria, too many harmful bacteria, or a lack of diversity in your gut microbiome. Dysbiosis in your gut can cause symptoms such as bloating, stomach pain, and changes in bowel habits (the frequency and consistency of your poop). Several factors can affect your microbiome and cause dysbiosis.

Diet

The microbes in your gut help you break down the food you eat, so it makes sense that your diet can have a direct effect on them. Your gut bacteria need fiber to survive. In exchange for dietary fiber, the bacteria give us beneficial SCFAs. A low-fiber diet makes it harder for beneficial bacteria to thrive and make SCFAs.

Research in mice has found that a diet high in fat can change the microbiome in a way that predisposes the mice to obesity and conditions related to obesity. Another study in mice found that eating the artificial sweetener sucralose (often sold as Splenda) can change the types of microbes in the gut and encourage inflammation. More research is needed to find out how these dietary habits may affect humans.

Antimicrobials

Antimicrobials are drugs that kill microbes that cause infection. Collateral damage to your gut microbiome is a common side effect of taking antibiotics (antimicrobials that kill bacteria). While antibiotics can help kill bacteria causing disease, they may also kill some of the good bacteria in your gut. This imbalance can result in an overgrowth of harmful bacteria, such as C. diff, which can cause potentially life-threatening diarrhea.

Chemicals

Exposure to certain chemicals can disrupt your gut bacteria, such as:

If you’re exposed to these chemicals, it may change your gut microbiome, affecting your risk of developing health conditions such as Alzheimer’s disease and heart disease.

Stress

High stress levels over a long period of time can cause dysbiosis that triggers inflammation. This inflammation may affect health conditions such as depression and inflammatory bowel disease (IBD).

What Health Conditions Are Related to Your Gut Microbiome?

As researchers have continued to learn more about how important your gut microbiome is to your health, they have also discovered how dysbiosis can affect it. A link between several health conditions and your gut microbiome has been discovered.

Inflammatory Bowel Disease

IBD is a group of autoimmune conditions that can cause severe symptoms such as diarrhea, stomach pain, bleeding, and weight loss.

Several studies have discovered that people with IBD have less diversity in their gut microbiome. This means that there are fewer types of bacteria. This is so common in people with IBD that it’s even part of the criteria to diagnose the disease.

Obesity and Related Health Conditions

Several studies in humans and mice have found that certain changes in the gut microbiome are linked to the development of overweight and obesity. Researchers are still learning how gut bacteria can influence this. It’s thought that it may be related to SCFAs and inflammation.

Your gut microbiome can also influence the development of other health conditions related to obesity, including high blood pressure and diabetes.

Heart Disease

Certain bacteria have been linked to the development of heart disease. Studies have found that people with heart disease often have dysbiosis, with fewer good bacteria and more harmful bacteria. Some of the harmful bacteria can make a chemical called trimethylamine-N-oxide (TMAO). TMAO plays an important role in the development of atherosclerosis (hardening of the arteries), a leading cause of heart disease.

Liver Disease

Researchers have found that specific changes in the gut microbiome are linked to a liver disease called metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD). MASLD is a condition linked to obesity that causes fat buildup in the liver that can eventually lead to serious liver problems and liver failure in some people.

Neurological Disorders

Neurological disorders are conditions that affect your brain or nerves. Recent research has found that dysbiosis may make people more susceptible to several neurological disorders, including:

Cancer

Studies have found that there may be a link between colon cancer and alterations in the gut microbiome. Researchers don’t know exactly how gut bacteria may affect the development of colon cancer. It’s thought that it may have to do with changes in the immune system.

Infections

If you have fewer good bacteria in your gut, it may be easier for harmful bacteria to find room to grow. Dysbiosis can also affect your immune system.

How Can You Take Care of Your Gut Microbiome?

Now that you know more about how your gut microbiome can affect your health, you may be wondering what you can do to help prevent dysbiosis.

Here are a few tips to help promote a healthy gut microbiome:

Talk to your physician about other ways you can help protect your gut microbiome based on your individual needs.