LifeCoachAdmin
We often think of the brain and the gut, or for that matter, all body systems, as separate. However, modern science is painting a different picture, one that shows that the gut and brain are in constant communication. This relationship is so profound, scientists have begun referring to the gut as our “second brain.”
This isn’t just a catchy metaphor, it’s a biological reality grounded in complex signalling networks. And it’s becoming clear that our mental health may be closely tied to the state of our gut microbiome. In this blog post, we’ll explore how gut health can influence mental health and ways you can enhance its symbiotic relationship.
What is the Gut-Brain Axis?
The gut-brain axis is a bidirectional communication system linking the central nervous system (the brain and spinal cord) with the enteric nervous system (your gut nervous system). These two systems talk via neural, hormonal, and immune pathways, with the vagus nerve being the most important player.
The vagus nerve is like a superhighway, transmitting information from the gut to the brain about everything from nutrient content to inflammation and microbial activity. When the vagus nerve is activated by things such as deep breathing or healthy gut signals, it tends to promote a calming, anti-stress effect.
Meet your Microbiome
Your gut microbiome is a population of trillions of bacteria, viruses, fungi, and even parasites living in your digestive tract. These microbes help break down food, produce vitamins, and control the immune system.
With respect to your brain, your microbiome produces chemicals such as serotonin, dopamine, and GABA, critical regulators of mood and anxiety. In fact, up to 90% of serotonin is produced in the gut.
Some gut bacteria also generate fatty acids, which have anti-inflammatory effects and may protect the brain from stress-related damage.
Mental Health and the Microbiome
Interestingly, research suggests that imbalances in gut bacteria, referred to as dysbiosis, may be linked to depression and anxiety. For instance, studies have found that people with depression often have less microbial diversity and lower levels of certain beneficial bacteria (Li et al., 2022). This has been verified in animal studies, where transferring gut microbes from anxious or depressed humans into mice caused the mice to develop similar behaviours (Kelly et al., 2016).
Although human trials are only just emerging, fortunately, small studies have found that probiotics can reduce symptoms of depression and anxiety, due to improved microbial activity (Schaub et al., 2022).
This research adds to the growing field of research that investigates this phenomenon, called “psychobiotics.”
What can you do for your Gut to Boost your Mental Health?
So all in all, while the field of psychobiotics is still in its infancy, supporting your gut health could be one way to support your mental well-being. Here are a few gut-friendly practices:
- Eat more fibre: Whole grains, fruits, vegetables, and legumes feed good bacteria, improve digestion, and reduce inflammation
- Include fermented foods: Yogurt, kefir, kimchi, and sauerkraut, are natural sources of probiotics
- Limit ultra-processed foods: High sugar and artificial additives may disrupt microbial balance
- Exercise regularly: Movement promotes healthy microbiota and improves vagal nerve activity
- Consider probiotics: But talk to your doctor before taking supplements
References
Kelly, J. R., Borre, Y., O’ Brien, C., Patterson, E., El Aidy, S., Deane, J., Kennedy, PJ., Beers, S., Scott, K., Moloney, G., Hoban, AE., Scott, L., Fitzgerald, P., Ross, P., Stanton, C., Clarke, G., Cryan, JF., & Dinan, TG. (2016). Transferring the blues: Depression-associated gut microbiota induces neurobehavioural changes in the rat. Journal of Psychiatric Research, 82, 109-118.
Li X., Jing K., Lu H., Li K., Zhang Y., and Hasichaolu. (2022). Exploring the Correlation between Changes in Gut Microbial Community Diversity and Depression in Human Populations. Biomed Res Int. 6334868.
Schaub, AC., Schneider, E., Vazquez-Castellanos, J.F. et al. (2022). Clinical, gut microbial and neural effects of a probiotic add-on therapy in depressed patients: a randomized controlled trial. Transl Psychiatry 12, 227.
