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We’ve all had a “gut feeling.” And while that popular saying is based on our intuition and instinct, our gut truly does play a role in our health and how we feel and function.

“Gut health” has become a trendy term in recent years. Our gut microbiome describes the microbes and their genetic material found in our gastrointestinal tract. And we know the bacteria in our gut affect everything from our digestion to our mental health.

What Is the Gut Microbiome?

You may think your gut microbiome is in your stomach, but it’s located in your large and small intestines.

“It contains all the microbes that reside within our intestinal tract,” says Gail Cresci, PhD, RD, a digestive disease researcher and registered dietitian at Cleveland Clinic. “And those microbes are comprised of bacteria, fungi, yeast and viruses.”

And we’re not talking about a few hundred microbes — it’s estimated that about 100 trillion microbes are found inside the human body, with many of them residing in our gut.

Importance of Your Gut Microbiome

Your intestinal tract is your largest immune system organ, with about 80% of your immune-producing cells living there.

“What we’ve learned over the years is that there’s a lot of crosstalk between your gut microbiome and your body,” says Dr. Cresci.

Your gut microbiome plays a role in digestion, metabolism and inflammation. When you’re an infant, your gut microbiome helps develop your gut immune system. When you’re an adult, it helps maintain it.

Symptoms of an Unhealthy Gut Microbiome

An imbalance of healthy and unhealthy microbes and their function is known as gut dysbiosis. “We’ve noticed that people with different mental health issues or mood disorders have gut dysbiosis, meaning there’s alterations in the composition of the gut microbiome and its function,” says Dr. Cresci. She warns that not all symptoms of an unhealthy gut microbiome are the same for everyone.

Some common symptoms may include:

  • Constipation.
  • Diarrhea.
  • Bloating.
  • Fatigue.
  • Acid reflux or heartburn.

If you have gut dysbiosis, it may be linked with other conditions like:

  • Diabetes.
  • Obesity.
  • Inflammatory bowel disease (IBD).
  • Irritable bowel syndrome (IBS).


1. Eat a variety of colorful fruits and vegetables.

Start by focusing on eating a variety of fruits and vegetables. You want to have “microbial diversity,” which will lead to better gut health. “It’s really looking at variety in our diet,” says Kristin Kirkpatrick, RD, a registered dietitian at Cleveland Clinic. “If someone tells me they eat kale all day, I think that’s a great habit to have, but it’s only one color. It’s only one type of nutrient they’re getting.” Instead, make a kale salad with other vegetables and fruits like peppers, tomatoes and berries.

2. Add fiber to your diet.

It’s recommended that women eat 25 grams of fiber per day and men 35 grams of fiber per day. Fiber helps keep your bowel movements regular, but also helps lower cholesterol and keeps your blood sugar levels from spiking. High-fiber foods include whole-wheat pasta, chickpeas, lentils and berries. “You want to have soluble and insoluble fiber,” says Kirkpatrick. “Soluble fiber swells in water — for example, oats from oatmeal. And insoluble fiber like nuts don’t swell. We want both of those types of it.” Dr. Cresci also suggests eating a diet low in animal meat and simple sugars and watching how much processed foods and refined sugar you consume.

3. Eat fermented foods.

Consider adding fermented foods like yogurt, kimchi and kombucha to your diet. These foods help introduce good bacteria into your gut microbiome and can lower your intestine’s pH level. Doing so can decrease the chance that bad bacteria survive and produce essential vitamins like B12 and K.

4. Reduce stress.

Your stress level can impact your gut health.“We’re learning more how stress can impact the gut microbiome,” says Dr. Cresci. “That means psychological stress, physical stress and metabolic stress.”Turn to relaxation techniques like deep breathing and meditation to help lower your stress. Plus, exercise regularly and prioritize sleep.

5. Maintain a regular eating schedule.

Besides eating a well-balanced diet, it’s also important when you eat. “You have a circadian rhythm, but your microbiome has a circadian rhythm, too,” explains Dr. Cresci. “If you’re eating late at night, your microbiome isn’t likely geared up to metabolize those nutrients as well.” Try to eat at the same time each day.

6. Avoid taking certain medications long term.

Sometimes, taking antibiotics is unavoidable, notes Dr. Cresci. But, she says they destroy the pathogens and attack good microbes in the gut, too. You should also avoid taking over-the-counter acid-reducing agents too long as they elevate your stomach’s pH. This allows any ingested pathogens a better change to survive, which can alter the microbiome.

7. Consider probiotic and prebiotic supplements.

Prebiotics, which can be found naturally in artichokes, apples and green bananas, are a type of fiber that supports the growth of healthy bacteria. Probiotics are live good bacteria that can maintain or help get to a healthy, balanced gut microbiome. There are two popular types of bacteria commonly found in supplement form: Lactobacillus and Bifidobacterium. Look for supplements that have a seal of approval from testing agencies like Consumer Reports or Consumer Labs. And there are many strains of probiotics, so it’s key to find one that works for the condition you’d like to treat. Some may provide relief if you have IBS or diarrhea. Others can help boost your immune system or reduce inflammation.

Overall, researchers are just beginning to understand how vital your gut microbiome is in relation to how the rest of your body functions. Even small changes in your diet and lifestyle can have a positive effect on your gut health.

“You have to look at where you are, what you’re willing to do in order to improve gut health,” advises Kirkpatrick. “A lot of times what happens is you feel the benefits so quickly that it’s easy to go on to the next step.”