"Gut health" is more than a wellness buzzword, experts say. Here's why it matters.

Gut health is everywhere. From products marketed specifically for gut health to videos with the hashtag #guthealth boasting more than 3.7 billion views on TikTok, the term has become a wellness buzzword — but experts say it's more than that.

Gut health isn't just a trending topic but an important aspect of health that impacts everything from obesity to cancer rates, says Dr. Aditya Sreenivasan, a gastroenterologist at Lenox Hill Hospital in New York. It can even affect mental health.

"The main reason it's becoming so common is that there's more and more data (and) understanding that what's happening in our gut or the (gastrointestinal) tract is associated with all kinds of much larger health outcomes — more than just what we typically maybe used to think of as GI issues like ulcers, gas bloating or colon cancer."

So, what exactly is "gut health" and why is it so important?

"When people talk about gut health, they're talking about the microbiome at large and its interactions with various bodily processes," says Dr. Shilpa Ravella, transplant gastroenterologist and assistant professor of medicine at Columbia University. She explains that the gut microbiome refers to the "trillions of bacteria, viruses and fungi that live in our intestines."

One of the most important ways the microbiome affects health is through its influence on our immune system, Ravella says.

"What happens is, from birth onto death, our microbiome actually helps to shape our immune system," she explains. "And this is important because we know today that inflammation is very relevant to our health. Low-level inflammation or chronic inflammation is tied to nearly all of our modern disorders. So when you have a gut microbiome that is an imbalance or dysbiosis, you tend to have more of this inflammation coursing through your body."

So while most may think of intestinal track as just a tube where food goes in and out, it's more than that. 

In a 2020 "60 Minutes" report, CBS News chief medical correspondent Dr. Jon LaPook spoke to Dr. Jeff Gordon, who has spent decades exploring the mysteries of the bacterial community in our gut and is recognized as "the father of the microbiome."

"(Microbes) help process the food that we consume, but they do a lot more than that. They make vitamins... they're able to produce essential amino acids, they're able to talk to our immune system and help educate the immune system."

In a landmark experiment, Gordon and his team made a lean mouse fatter by giving it the bacteria of a fat mouse, suggesting that part of the cause of obesity might be the types of bacteria that are in the microbiome.

"We see that individuals who are obese have a less diverse microbial community compared to individuals who are lean," Gordon explained.

In 2021, a study found the gut microbiome can possibly indicate whether a patient with rheumatoid arthritis will improve in their condition over time. And research on the connection between a healthy microbiome and heart health, diabetes and other conditions continues. 

Products promising gut health benefits are proliferating, including drinks marketed to those looking to support a healthy gut. At the same time, scientists' understanding of probiotic supplements is also shifting. Once viewed as a useful daily dose of commercially manufactured mixtures meant to replicate the healthy bacteria found inside our bodies, now some experts say these products might not be as helpful as once thought.