Gut feelings: Your superpowered sixth sense

Remember meeting someone for the first time and you immediately “hit it off”? Talking to that person felt like talking to a best friend you’ve known for years. Time flew by and you likely felt a funny, but good feeling in your stomach during the interaction – butterflies.

When someone tells you they have “butterflies in their stomach” you know exactly what they mean. There aren’t any insects beating their wings against the walls of your friend’s intestine. The metaphor describes a giddy, nervous feeling that starts in the abdomen and spreads through the entire body.

Some might regard this feeling as a “sixth sense”, but where does it come from?

Humans have long been interested in understanding how the gut works and its connection to the brain. After all, gut feelings are an evolutionary mechanism that helped keep us safe and alert as hunters and gatherers. There is a rich history of research and medical techniques to examine the gut and its elusive connection to the brain that date back to ancient civilization.

Ancient Greeks and the Dong-jin dynasty of China used fecal matter transplants to treat patients with gastrointestinal problems and noted psychological side effects. In the 18^th and 19^th centuries physicians continued to explore the connection between gastric problems and disorders of the brain, blaming psychological symptoms on digestive issues and vice versa. In the late 20^th century, imagining technology allowed us to visualize the gut and brain in its living form for the first time. 

"Humans have long been interested in understanding how the gut works and its connection to the brain. After all, gut feelings are an evolutionary mechanism that helped keep us safe and alert as hunters and gatherers."

-- Rachel Edens

The 21^st century has blown the doors open on research into the physical and mental connections of the gut and the brain. We now understand that the bodily circuitry responsible for sensing and interpreting our “gut feelings” is the gut-brain axis (GBA). More specifically, the GBA is the communication between two distinct but connected parts of your nervous system: the central nervous system (CNS), which describes the brain and spinal cord, and the enteric nervous system (ENS), which protrudes into the gut tissue.

More recent discoveries have revealed that your gut microbiota, or the community of bacteria in your gut, interacts directly with the neurons of the ENS by releasing neurotransmitters. Gut microbes can also modulate hormone release from the gut that affect the CNS. Researchers have found strong correlations between patients with depression and anxiety and an unhealthy gut microbiome, defined by an increased presence of bad or pathogenic bacterial species. Conversely, establishing a healthy gut microbiome community has been linked to the improvement of mental disorders such as anxiety and depression.

Popular media has also caught on to the trend of taking care of your gut health. Many health and fitness influencers can be seen promoting probiotics and certain diets meant to promote the healthy bacterial communities in your gut, thus improving overall and mental health. While the core of these ideas is true, they can often be sensationalized for the sake of online interaction.

What does the research show we can do to promote and support our gut health? And how does that actually effect our mental health?

A well balanced, high fiber diet has been shown to provide the nutrients your healthy gut microbiota needs to truly thrive. Additionally, introducing good microbiota to the gut through active cultures such as fermented foods and probiotics can give your gut the boost it may need to establish healthy communities. This can be especially important after a round of antibiotics that deplete your healthy microbiota as it was clearing an infection.

Your gut microbiota, like you, function on a 24-hour cycle. Meaning they’re happiest when they receive nutrients at the same time each day and can perform their regular functions on a schedule. Therefore, you can also support your gut health by eating your meals at the same times each day and spacing them apart, so your microbiome has time to breakdown all the great nutrients you provide it!

Research has shown that simply following a well-balanced diet with scheduled mealtimes is directly associated with improvement of the health of the gut microbiome. We also know that the gut microbiome interacts directly with the brain via the CNS and ENS, and a healthy gut is correlated with lower rates of mental disorders. However, the research is still complicated. Patients with the happiest gut microbiota who eat a healthy diet often also exercise multiple times a week. Dopamine release from regular exercise is also extremely effective at protecting the brain from disease.

The GBA is a complicated system that needs further exploration to be more fully understood. However, we can appreciate its sensitivity and complexity more than ever before. Your gut feelings aren’t a biological fluke, they’re your superpowered sixth sense!