Scientific consensus tells us that the number of microbes in our bodies exceeds the total number of human cells. These microbes represent 99% of our genetic material! They were here first, have co-evolved with us, and continue to play crucial roles in development as well as lifelong health.
In this article, we will discuss the roles our microbes, commonly referred to as “bugs,” play in brain development, cognitive function and overall wellness throughout different states in life. We will also highlight the supportive role of specialized probiotics or what we now refer to as “psychobiotics.”
Early Life
A large body of scientific evidence has demonstrated the importance of early life exposure to microbes. These friendly bugs are instrumental to the development of our gut microbiome, immune system, brain and nervous system., In cases where the normal exposure is absent or limited, such as with C-section births, there is a higher risk of developing allergies and autoimmune diseases.
Preclinical studies have also demonstrated that C-section delivery is associated with social impairment and anxiety-like behaviors. And although there is limited human clinical trial data that makes this connection clear, Professor John Cryan, PhD, describes related unpublished data from his lab, where Irish medical students were subjected to humane stressors and their responses were evaluated.
Students born by C-section experienced more significant perceived psychological stress (PSS) as well as exaggerated immunological response, suggesting our brains are indeed influenced by the bugs we meet at birth.
In fact, leading microbiome and gut-brain axis research laboratories have supplied us with convincing data to support this hypothesis. Findings have shown that a lack of resident microbes will negatively impact nerve conduction in the prefrontal cortex of the brain responsible for high level processing.
A bug-free environment is also associated with the disruption of new neuron formation in the hypocampus, the area in the brain responsible for memory and learning. Critical to social behavior, fear and anxiety response, the brain’s amygdala is also altered, both functionally and structurally, by disruptions in the microbiome.
The sobering reality is that all of these factors have been linked to a variety of neuropsychiatric disorders ranging from autism to anxiety.
The good news is that activities such as breastfeeding, quality probiotic supplementation and early exposure to helpful bacteria can reduce these risks in C-section babies. Supplemental probiotics and prebiotics can provide for robust microbiome diversity, as well as support normal brain development and function .
Teenage Years
As any parent can attest, the adolescent brain undergoes many changes and hormones are not the least of them.
Interestingly, one of the primary gut-to-brain/brain-to-gut communication channels, the hypothalamic-pituitary-adrenal (HPA) axis, is also undergoing its own developmental process during these years. Chronic stressors in adolescence can result in an HPA axis imbalance, impacting cognition, decision making, and mood over the long term.
Here again, there is some good news. A healthy, whole food diet, regular exercise, adequate sleep, and quality probiotic intake can go a long way toward a balanced microbiome and healthy gut-brain axis.
Aging
During the childhood and adolescent years, the gut microbiota is dynamic and evolving. Our bug population does, however, get more stable as we enter adulthood. This stability is then followed by reduced diversity with both age and illness.
To explore this phenomenon, a research team developed the human microbiome aging clock. Amazingly, their approach has successfully predicted human age within five years. The data from their lab and others has suggested that age-dependent changes in microbiota diversity may influence frailty, immune response, and related disease onset.
Another key area of interest within the aging brain lies with its resident immune cells. Acting as scavengers within the central nervous system, microglia are the brain’s housekeepers. And what you might think of as independently functioning cells, these microglia are found to be immature and functionally impaired in the absence of a balanced microbiome.
Lastly, it is important to recall that our gut microbes are instrumental in the production of all five human neurotransmitters – GABA, serotonin, acetylcholine, norepinephrine, and dopamine – as these substances play an integral role in mood and cognition across the lifespan.
The Promise of Psychobiotics
First coined by the team of John Cryan and Ted Dinan at the Alimentary Pharmabiotic Center (APC) at University College, Cork (Ireland), the term “psychobiotics” refers to beneficial bacteria (probiotics) or support for such bacteria (prebiotics) that influence bacteria–brain relationships.
Psychobiotics are able to exert anti-anxiety and antidepressant effects through the gut’s own nervous system as well as the immune system. But not all probiotic strains are psychobiotic, and not all probiotic blends claiming psychobiotic characteristics are backed by scientific evidence.
On the other hand, OMNi-BiOTiCÒ STRESS Release is a clinically proven psychobiotic formulation that has demonstrated positive influence in both functional (fMRI) and psychological measures toward improved mood, memory, and stress management.
It is abundantly clear that our bugs play a vital role in our mental function and overall wellbeing over the entire lifespan. And with the American Psychological Association reporting that more than 80% of Americans are still experiencing prolonged stress in 2021, a sound, scientifically based psychobiotic makes all the sense in the world.
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