Gut health is increasingly a big business. Whether you’re browsing supplements at the grocery store, scrolling social media or even buying soda, you’re bombarded with products promising to feed your microbiome.
Influencers, fitness gurus and celebrities say a healthy gut is the key to wellness. The concept is linked to curing digestive diseases, improving immunity and regulating body weight.
But is this health craze based on real science? Michigan State University researcher Robert Quinn says the answer is yes.
The associate professor at the College of Natural Science Department of Biochemistry and Molecular Biology has devoted much of his career to studying the gut microbiome. He says gut health isn’t just a catchphrase – it’s a crucial part of digestion that, when out of balance, can cause chronic illnesses and make us feel sick.
What is the gut microbiome and what does it do?
The gut is the entire gastrointestinal, or GI, tract, from entrance to exit, Quinn said. Much of this tract, including the stomach, isn’t hospitable to microorganisms, but the colon and lower tract are home to trillions of bacteria. These microbes break down fiber and food that isn’t digestible by human organs.
“Food makes it through that first 70 percent of the journey through your GI tract to get into the colon, and then the microbes do their thing,” Quinn said. “What the field has shown is that when the microbiome ferments fiber, it makes a lot of good products that are very healthy for us.”
A healthy microbiome isn’t pseudoscience – it’s real, and necessary. The products it creates, including butyrate and indoles, can do everything from supporting gastrointestinal health to regulating blood sugar and inflammation. The human body has relied on compounds produced by the microbiome for millions of years to stay healthy.
Everything changed after the Industrial Revolution. Humans shifted away from food grown and harvested close to home instead to a processed and preserved diet. Most people’s gut microbiome fell into a state of dysbiosis, meaning an imbalance in the bacterial ecosystem.
“There are millions of years of human evolution preceding the last 150 or so, when all of a sudden we fundamentally changed how we eat and where our food comes from,” Quinn said. “To promote a healthy gut ecosystem, you need to feed these microbes the type of diet they’re designed to eat.”
An unhealthy gut is linked to inflammatory bowel diseases, including irritable bowel syndrome, Crohn’s disease and ulcerative colitis. It’s also connected to obesity, chronic inflammation and diabetes. At its most extreme, dangerous bacteria such as C. difficile can colonize an unhealthy gut, with deadly consequences.
What foods are good for your gut?
Most people don’t have a healthy gut microbiome, not through any fault of their own but because of our modern diet. The good news is, we can improve our gut health with a long-term concerted effort.
Quinn says after 10 years of research, his best advice is to consume fiber, and lots of it. A diet of whole foods like apples, avocados and oatmeal – foods that more closely resemble what our ancestors would have eaten – help feed a vibrant microbiome.
One of the best high-fiber foods for your gut is the unglamorous prune. Not only is it packed with fiber, but it also contains complex sugars that feed the microbes in your colon.
Fermented foods, like sauerkraut, yogurt and pickles, also make for a happy gut microbiome. This ancient method of preservation is found in cultures throughout the world. Many, like kimchi in Korea, are also full of fiber.
“There’s a lot of literature on fermented foods,” Quinn said. “They seem to have an effect on your microbiome. They can change it over time. It’s still the same idea that if you give the microbes fiber, they’ll produce the products that we need, and that we’ve probably been missing since the Industrial Revolution.”
What about kombucha and probiotics?
Grocery stores and pharmacies are full of products promising to improve gut health. Some of them work, Quinn said. Others, the jury is still out.
Your friend who’s always touting the health benefits of kombucha? Quinn says they’re not wrong. Kombucha is a great example of a fermented food that promotes a healthy gut.
The answer isn’t so clear-cut on probiotics, a product sold in the vitamin aisle claiming to boost your gut microbiome. While thousands of studies have been done, Quinn said the literature is complicated. Some of the most validated evidence of positive effects are in cases where probiotics are taken after a round of antibiotics, which can devastate gut microbes.
Quinn compared taking probiotics to introducing a fish from Lake Ontario into an ocean coral reef. The fish can’t survive because it isn’t adapted to that environment.
“There’s this ecology that makes probiotics challenging, because you’re putting a foreign organism into a well-established ecosystem of organisms that are already adapted to live there,” Quinn said. “It’s hard to get them to establish, but that doesn’t mean they’re bad. It might not work, but it’s almost certainly not going to cause any harm.”
Can food heal like medicine?
A popular mantra among the wellness community is “food is medicine.” Quinn says food can indeed help you feel better. Intentionally feeding your microbiome over time could help you shake that chronic unwell feeling, and it could prevent digestive disorders and other chronic illnesses.
At the same time, food isn’t a replacement for following a doctor’s recommendations.
“Food might be medicine, but medicine is also medicine,” Quinn said. “You can’t just eat avocados if you’re sick. If your doctor is telling you to take an antibiotic, take the antibiotic. Don’t try to outsmart your doctor.”
How seriously should we take gut health?
Gut health is serious, but it doesn’t need to be a source of stress. Quinn says it’s an opportunity to experiment with new foods and add something fun to your diet. Try dishes from other cultures and maybe even throw chopped prunes into your yogurt or oatmeal.
A high-fiber, gut-healthy diet is a low-risk way to feel better this new year.
This story originally appeared on the College of Natural Science website.
