How to Feed the Brain in Your Belly

There has been a longstanding metaphorical connection between the brain and the gut, illustrated by expressions such as “trust your gut” and “gut instinct.” Now we’re learning about the physiology behind the metaphor—the dimension of intelligence that actually comes from the gut. Those “butterflies” or that “knot” in your stomach are signals from the brain in your belly telling you to be nervous. This “belly brain” even has a scientific name—the enteric nervous system (ENS)—and the 100 million nerve cells that make up this brain are hidden in the walls throughout the digestive tract.

This sophisticated superhighway that connects the brain in your head to the brain in your gut is getting a lot of attention in the scientific literature lately, especially when it comes to mental health issues such as depression and anxiety. In fact, our belly brain may influence our mental health as much as our head brain. And if this is the case, it makes sense to find out how to properly “feed” that belly brain. As it turns out, one of the best ways to support your belly brain is with bacteria—namely, good bacteria known as probiotics. These good bacteria take up residence in the gut and can have significant influence on our health in ways that go far beyond curing digestive disturbances such as gas, bloating, and diarrhea. Healthy gut bacteria can make you feel happier and less anxious.

Naturopathic physician and bacteria expert Dr. Mark Davis explains, “In the past decade, there have been a handful of good studies and one great meta-analysis looking at what happens to mood in animals and humans who take a probiotic versus a placebo.” Davis says these studies hint that probiotics can help people be less anxious and depressed and even help them dwell less on pain and ruminating thoughts. “Since probiotics appear to be so overwhelmingly safe, I for one am willing to take the hint,” concludes Davis, who is the founder and director of the Bright Medicine Clinic in Portland, Oregon.

“There is more acceptance of probiotics, not just within the gastrointestinal medical specialty, but in medicine in general,” explains Eamonn Quigley MD, who is the past president of the American College of Gastroenterology and of the World Gastroenterology Organization and the head of Gastroenterology and Hepatology at Houston Methodist Hospital. Quigley says there are many new potential roles for probiotics when it comes to disease prevention and treatment.

Thanks to emerging research involving the belly brain, we can add anxiety, depression, and other mental health issues to the growing list of conditions that can be positively influenced by probiotics.