Our digestive tracts are not just for processing food. They are also the home to countless microorganisms that live inside our bodies and aid our survival. Imbalances in the bacteria in our gut can lead to Irritable Bowel Syndrome (IBS), diabetes, skin problems, bad breath, suppressed immunity, allergies, and iron-deficient anemia. Oftentimes, a healthy gut can mean a healthy body. In addition to these bacteria, our gastrointestinal tracts also house some 500 million neurons, which experts refer to as the enteric nervous system (ENS). Colloquially, many researchers have labeled the ENS our “second brain.”
Though the ENS does not think—we do not rely on it to complete our math homework or to remember a loved one’s birthday—but evidence suggests that it does play a major role in our moods. When we feel butterflies or a knot in the pit of our stomachs, we are likely receiving signals from our second brains. Most of us think as the brain as the control center of the body: our brains send messages to our extremities to cue them to do what we need them to do. The pathway between the brain and the ENS, however, is bidirectional, which means that the gut can send messages to the brain in addition to receiving messages from the brain. Scientists refer to the communication that happens between our guts and our brains as the gut-brain axis (GBA).
Messages transmitted along the GBA, evidence suggests, can account for much of how we feel. Research has shown that those with healthy and diverse gut bacteria are less likely to suffer from anxiety and depression, while those with less healthy digestive systems can fall prey more easily to these disorders. Similarly, because the GBA is bidirectional, studies have indicated that IBS and functional bowel problems can be treated with antidepressants and therapy, suggesting a strong connection between the gut and the brain.
A balanced diet and childhood exposure to many different sorts of bacteria are generally thought to promote gut health. On the other hand, growing up in an overly sterile environment, a diet low in nutrients, and frequent antibiotic consumption leads to imbalances in the gut’s bacterial ecosystem. Ways to boost gut health are to eat a varied and nutritious diet, and to take probiotics, which can be found as a supplement or in certain foods, like Greek yogurt and kombucha.
In order to ensure that we are mentally well, we must consult with mental health and medical professionals and follow the advice that they give. A consistent, nutritious diet high in probiotics, though, might just give us that extra boost we need to start feeling great both physically and mentally.