You've probably heard the term "gut health” and know that "good” gut health is desirable. But what does it really mean to have a healthy gut? It means having the right balance of tiny bacteria and other microbes in your digestive tract. Researchers are increasingly discovering ways these microorganisms contribute to overall health.

"A healthy gut means you have a stronger immune system, a better mood, effective digestion that's free of discomfort and a healthy brain and heart,” says Sabine Hazan, M.D., a gastroenterologist, founder of Ventura Clinical Trials in Ventura, California, and author of "Let's Talk S—.

What Is Gut Health?

Gut health refers to the health of your gastrointestinal (GI) system, including digestion, a normal and stable microbiome, absence of GI illness, an effective immune system and more. The health of your GI tract is linked to other aspects of overall health, such as emotional stress and chronic illness, according to experts at the Ohio State University Wexner Medical Center. Additionally, research suggests that certain foods, behaviors and environments may affect an individual's gut health.

Your gut communicates with your brain via hormones and nerves that help promote and maintain overall health and well-being. Typically, a healthy gut contains good bacteria and immune cells that fight off disease-causing bacteria and viruses.

About Your Microbiome

The microbiome is all of the bacteria, viruses and fungi that inhabit the human body, says Dr. Hazan.

These bacteria are everywhere, including the skin, mouth, throat, stomach, colon, uterus, ovarian follicles, prostate, lungs, ears and eyes. "You name it, and there are microorganisms nearby,” Dr. Hazan says, adding that research has identified around 10,000 different microbial species in the human body.

Microbiologists divide bacteria into two categories: aerobic, meaning they require oxygen, and anaerobic, meaning they don't require oxygen. "Bacteria that live on the skin are aerobic while those that thrive in the gut are usually anaerobic,” Dr. Hazan explains. "The microbiome is the key; it influences all sorts of health conditions from cancer to COVID-19.”

Why Is Gut Health Important?

Your gut—otherwise known as your digestive system or your gastrointestinal (GI) system— digests the foods you eat, absorbs nutrients from it and uses those nutrients to fuel and maintain your body.

"The gut plays a huge role in the health and well-being of our bodies,” says Alicia Romano, a specialized clinical dietitian at Tufts Medical Center in Boston and a spokesperson for the Academy of Nutrition and Dietetics. In addition to digesting food and absorbing nutrients, "the gut is in tight communication with the brain, playing a constant game of telephone and influencing a number of factors, including immune activity, GI muscle contractions and fluid secretion. And the gut is a key player in the body's immune system—over 70% of your immune cells reside in the gut.”

5 Science-Backed Ways to Improve Your Gut Health

Certain foods and healthy lifestyle habits can improve your gut health naturally.

1. Eat Fiber-Rich and Probiotic-Packed Foods

Fiber is a plant-based nutrient that reduces the risk of metabolic diseases by stimulating the growth and diversity of good bacteria in the gut, research suggests. Sweet potatoes, spinach, beets, carrots and fennel are full of naturally gut-enhancing fiber. Besides fruits and vegetables, whole grains are a rich source of fiber, too.

Fermented foods like yogurt, kimchi, sauerkraut and kombucha are also prized for their gut-boosting abilities, thanks to the presence of probiotics. Yogurt specifically may help calm gastrointestinal conditions like diarrhea, inflammatory bowel disease and constipation. One study found people who eat yogurt regularly have more lactobacilli, a gut-benefitting bacteria, in their intestines, as well as fewer enterobacterium, a type of bacteria linked with inflammation.

2. Exercise Often

Movement is medicine for so many parts of the human body, including the microbiome. In both animal and human studies, researchers have found that exercise promotes an increase in diversity of healthy bacteria in the gut.

While several studies highlight the roles exercise and diet can play together in positively impacting gut health, a 2019 review specifically reported that exercise has the potential to alter gut bacteria composition and functionality independently of diet. Researchers found longer workouts and high-intensity aerobic training, in particular, contributed most to gut bacteria diversity and function in relation to overall wellness. They also observed that lean people are more likely to reap the gut health benefits of exercise than individuals with overweight or obesity.

3. Limit Your Alcohol Intake

Drinking too much may negatively affect your microbiome, too. Repeated alcohol use is linked to gastritis, an irritation of the gut in which it becomes inflamed. Such inflammation can lead to heartburn, chronic discomfort, ulcers and bacterial infections.

Drinking too much is also associated with intestinal inflammation, which is a sign of an unhealthy gut. Research suggests that this kind of inflammation alters the microbiota—including how well it works—and can throw it off balance.

4. Reduce Stress Levels

Stress isn't just mental: Think about those butterflies you feel when you're excited or anxious. Experts in gut health often cite the "gut-brain connection” and refer to the gut as "the second brain.” While we don't know everything about their relationship, we do know that mental health and the gut are intimately connected.

Research suggests anxiety and depression are affected by the gut and vice versa—they can increase the risk of IBS, and people with IBS are more likely to experience these mental health disorders.

Finding ways to manage your mental health and stress levels may help reduce uncomfortable GI symptoms and get your body back in balance. Don't know where to start? Try adding some physical activity to your day. Something as simple as a daily walk might improve gut health, as research suggests exercise can increase the quality and quantity of health-boosting gut microbes.

5. Consider a Supplement

Probiotic supplements have become increasingly popular as word of the importance of gut health continues to spread. While probiotic supplements aren't a panacea for gut health, there's some evidence they can give the microbiota a boost and restore gut health under certain conditions.

Probiotics may be beneficial for certain health concerns, such as preventing infections while taking antibiotics and improving inflammation in individuals with inflammatory bowel disease who also have a condition called pouchitis. However, not all probiotics are right for all health conditions, and most probiotics are likely limited in their ability to move the needle when it comes to gut health—especially if other healthy choices are not employed.

If you're interested in a probiotic supplement, talk to your doctor. While such supplements are mostly considered safe, especially in healthy people, the risk of harmful effects is greater in people with compromised immune systems.

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Signs You May Have an Unhealthy Gut

One less-than-pleasant sign something's up with your gut? Unfamiliar changes in your poop.

"If you notice abrupt changes to your stool length, color or consistency, this may be cause for concern,” Dr. Hazan says. "Normal stool should be brown and never include blood.”

Because so much of the population experiences issues with their bowels during certain points of their lives, doctors developed the Meyers Scale (aka Bristol Scale) to help patients describe their poop "without bringing in colored photos,” Dr. Hazan says. Different numbers on the scale are associated with different bowel movement issues, so consider checking out the scale to help communicate your concerns to your physician.

Still, it's important to remember what's considered normal to you. "If your poop has looked like Silly Putty your whole life and you don't experience any pain, this could be your normal,” says Dr. Hazan, explaining that describing something as "normal” is all relative.

Beyond the status of your bowel movements, there are other signs your gut could use some attention. While everyone needs to be concerned about their gut health, Dr. Hazan says, the following symptoms may signal that your gut health could use some attention. Schedule some time with your physician if you experience:

• Abnormal weight loss
• Anemia diagnosed by your doctor
• Change/pain in bowel habits
• Rectal bleeding

How to Check Your Gut Health

If you're concerned about the status of your gut, there are a number of routes available for monitoring and evaluating your gut health, both at home and with your health care provider.

Take note of symptoms like stomach pain, gas, bloating, nausea or diarrhea. These symptoms often resolve themselves over time, but may require assistance from your doctor if they become chronic issues.

If symptoms persist, it may be beneficial to undergo a stool analysis with your health care provider. Stool analysis consists of a series of tests that analyze a stool sample to diagnose and treat certain GI conditions.

When to See a Doctor

If you experience symptoms including a change in bowel habits, unexplained stomach pain, abnormal weight loss or blood in your stool, it may be beneficial to visit a health care provider. Your doctor may perform a series of tests to help diagnose, treat or rule out certain health conditions.

Frequently Asked Questions (FAQs)

What causes a weak gut?

Gut issues may arise due to an overgrowth of bad bacteria, loss of good bacteria or a general decrease of microbiome diversity. These changes in an individual's microbiome may be caused by lifestyle factors such as smoking, consuming alcohol and being sedentary. Other factors that may have a negative impact on your gut health include poor sleep quality and consuming too much red meat and refined sugars.

How can I make my gut health stronger?

Ways to improve your gut health include eating fiber-rich and fermented foods, getting regular exercise, limiting your alcohol consumption and managing stress. Additionally, consult with your doctor to determine if you may benefit from adding a probiotic supplement into your routine.

What are the worst foods for your gut health?

Foods that may have a negative impact on your gut health include red and processed meats, ultra-processed foods (like soft drinks, fast food and packaged salty snacks), refined sugars and certain artificial sweeteners like aspartame, sucralose and saccharin.

What are the best foods for your gut health?

The best foods for a healthy microbiome include fiber-rich fruits and vegetables such as bananas, asparagus, artichokes, onions, leeks and garlic. Other fiber-rich food sources that promote a healthy gut include beans and whole grains such as wheat, oats and barley. Additionally, fermented or pickled foods like kimchi, sauerkraut and kefir may help promote gut health.

What are the best supplements for gut health?

Probiotic supplements may help fight disease-causing bacteria and absorb nutrients, as well as aid in digestion. Additionally, these supplements may help improve or reduce symptoms of irritable bowel syndrome like diarrhea and constipation. Consult with your doctor to determine if you would benefit from adding a probiotic supplement into your routine.

Sources

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