Recent medical research on the gut-brain connection supports the importance of the relation between the healthy gut and a healthy brain. A major mediating element is our microbiome, largely the gut’s bacterial colonies. A documentary, “The Gut: Our Second Brain,” available on Amazon Prime presents an amazing and artistic view of how our intestinal tract and central nervous system interact (https://www.amazon.com/Gut-Our-Second-Brain/dp/B01MY5C9VI).
Many brain and mood conditions are affected by alterations in gut bacteria. Among these are anxiety, depression, autism, schizophrenia, Parkinson’s disease, and Alzheimer’s. Frailty in older adults was found to be correlated to the decreased variety of gut bacteria in institutionalized seniors versus those living in the community. Conditions like irritable bowel syndrome (IBS) are highly affected by anxiety and stress. Gut bacteria in IBS patients are markedly different than in controls without the condition.
To back up briefly, we have trillions of bacteria in our gut that are commensal, meaning they live inside us as friendly partners, help us digest food, protect our immune system, and affect the production of neurotransmitters. These bacteria, our microbiome, weigh up to 6 pounds and have more DNA than our entire body by a factor of at least a hundred. In other words, we’re more bacterial DNA than human DNA.
These co-habitants in our body can be altered by many factors: C-section versus vaginal birth, antibiotics, diet, medications, stress, supplements, genetics, and more. Emerging science points out that the architecture of this mix of over a thousand bacterial species, now identifiable through metadata analyses of their DNA in stool samples, is a potential for therapeutic intervention.
Probiotics, prebiotics, antibiotics, diet, omega 3 fatty acids, and fecal bacterial transplants have been discovered to alter the course of medical conditions like IBS, severe diarrhea from Clostridium dificile, and some psychiatric conditions. So-called psychobiotics have an increasing present and future role in the treatment of some mental conditions as well as neurodegenerative diseases.
This is a radically different, evolutionary approach to treatment of chronic disease. Instead of just stomping out infectious bacteria, we’re discovering ways to alter the health-promoting bacteria in our guts. The feedback loop to the brain involves the autonomic nervous system through the vagus nerve, neurochemical transmitters, the immune system, and the integrity of gut mucosal barrier.
The science of the ecology of the microbiome and gut-brain axis is evolving rapidly. Yet some things are still unclear such as what are optimal diets, specific probiotic recommendations, dosages, the impact of genomic variations, and to what degree our microbiome affects our mood and brain health. More research is clearly needed. For now:
1. Eat fermented foods on a regular basis, e.g., yogurt, sauerkraut, kimchi, kefir, tofu to keep feed gut bacteria.
2. Eat abundant prebiotics, which are colon food for our gut bacteria and include non-digestible fibers and plant-based foods in general.
3. Replace gut bacteria with probiotic supplements if you need to take antibiotics and consider regular use.