A Healthy Brain is a Happy Gut
**This post was originally published in the January 2022 staff newsletter for Capernaum Pediatric Therapy
How many of you experience a stomachache or nausea when stressed? Maybe you feel ‘butterflies’ in your center when nervous or anxious? What about that pesky back and neck pain, or even migraine headaches after a long day?
You are not alone! These are all very common physical responses to emotional stressors. As Dr. Jennifer Guadiani writes in her book Sick Enough, “The mindbody connection is real and cannot always be perfectly explained or measured.” She goes on later to write “Our emotional state affects our physical symptoms.” In other words, our bodies and our minds are very intertwined; how we feel emotionally can absolutely impact how we feel physically, as seen in the examples above.
In addition to the overall body and mind interconnectedness, there is also a specific communication pathway between the brain and gastrointestinal tract, typically referred to as the mindgut connection or gut-brain axis. The vagus nerve, the longest nerve in the autonomic nervous system, acts as a two-way street between the brain and entire GI system (think brain to colon). When we are experiencing any sort of emotional or physical stress, the vagus nerve sends signals from the brain to the GI tract that the body is in “fight or flight” mode, so our gut reacts accordingly (slowing digestion, hormone secretion, and nutrient absorption as a means to preserve energy). This stress response can also alter our gut microbiota (the necessary bacteria in the gut).
It seems every healthcare provider in recent years has been promoting the importance of our gut microbiome, yet you may ask yourself, but why does this matter? As mentioned above, the vagus nerve works as a two-way street. This means bacteria in our gut can also communicate back to the brain via this same pathway! Research has shown these “good bacteria” in our digestive tract not only enhance nutrient absorption and regulate digestive functioning; they also help promote immune support, influence neurotransmitters and cell neogenesis, as well as impacting learning, mood, and anxiety. Most people are also surprised to learn that our gut microbiome has a role in producing serotonin and mood stabilizers. In fact, 90% of serotonin (a key mood hormone) is made in the gut! If that wasn’t enough, the latest research shows a correlation between the types of microbial diversity (and even reduced microbial diversity) in people with depression and other mental health conditions. In a nutshell, the more diversity of microbes in our gut, the better health outcomes.
Below are other key points from recent scientific research related to the gut microbiome, infancy/childhood, trauma, and feeding:
An infant’s overall microbiome at birth is impacted by delivery method, breastfeeding vs. formula fed, maternal health, living environment, and overall genetic predisposition.
Changes in the gut microbiome have been correlated with allergies in babies.
Children with history of early caregiving disruptions had distinctly different gut microbiomes than those raised with biological parents.
Children with past caregiving disruptions showed higher levels of GI symptoms (stomachaches, constipation, nausea, vomiting).
The good news! Practicing stress management, consuming a variety of foods/food groups, and addressing any underlying health conditions are small steps we individually can take to support our own mental and physical well-being. There is mixed scientific evidence whether probiotic supplements are necessary for most people’s gut health, namely due to the varying diversity and microbial needs person to person. A positive takeaway is that functional medicine is still such a new and emerging area of study, so the entirety of how the gut brain axis is involved in our health is still relatively unknown! There is always more to be learned in the nutrition field as research continues to evolve. I’ll leave you all with this: While the state of your gut has shown to influence mood, the reverse is also true: “A healthy brain = a happy gut.”
Resources:
Sick Enough by Dr. Jennifer Guadiani, MD, CEDS, FAED
Gut Instincts webinar by Dr. Heather Finley
https://microbiomejournal.biomedcentral.com/articles/10.1186/s40168-017-0260-z
https://www.dougcookrd.com/gut-brain-mental-health-dietitian/
Inner Workings: Can feeding the gut microbiome treat malnutrition? | PNAS
The importance of the microbiome in pediatrics and pediatric infectious diseases (nih.gov)