It is well-established that our gut bacteria affect our mental health. This topic is worth a thousand articles, so this general overview will serve as a foundation for future articles on mental health. 

“Patients with various psychiatric disorders including depression, bipolar disorder, schizophrenia, and autism spectrum disorder have been shown to have significant differences in the composition of their gut microbiome. Enhancing beneficial bacteria in the gut, for example, through the use of probiotics, prebiotics, or dietary change, has the potential to improve mood and reduce anxiety in both healthy people and patient groups.” (Butler, Mörkl, Sandhu, Cryan, and Dinan, 2019)

From Gut to Brain

“Hormones, neurotransmitters and immunological factors released from the gut are known to send signals to the brain either directly or via autonomic neurons.” (Clapp, Aurora, Herrera, Bhatia, Wilen, & Wakefield, 2017)

The link between our gut and our brain is a two-way street, and we are learning more about it everyday. Our gut microbiome can affect our brain via neural, endocrine, and immune system pathways, both by design and by force/error. In other words, bacteria play a role in guiding our thoughts and moves, and generally this is expected by the body, or at least we have adapted to it, but occasionally the bacteria play roles that we are not as prepared for. 

The gut microbiome has specifically been shown to:

• play a major role in the hypothalamic–pituitary–adrenal (HPA) axis, which mediates the stress response and is closely connected with depression and anxiety disorders

• significantly influence the immune system and may represent link between immune dysfunction and mental illnesses such as depression and schizophrenia

• directly produce various neurotransmitters such as serotonin, noradrenaline, dopamine, and γ-aminobutyric acid

• control tryptophan metabolism and serotonin production

(Butler, Mörkl, Sandhu, Cryan, and Dinan, 2019)

Since this only scratches the surface of the way our body and bacteria work together, you can expect more articles from Your Microbiome Advocate that take a closer look into specific mental illnesses and interventions. 

Science in its Infancy

The good news is that manipulating the gut microbiome is being studied, often with promise, as an intervention for many mental health issues. Probiotics, dietary changes, fecal microbial transplants, and more, are some methods for adjusting and improving mental health.

The bad news (for now) is that Your Microbiome Advocate is not endorsing any specific intervention, but simply sharing what is on the horizon and what future generations might look forward to. The science is young- it was only ten years ago or so that these concepts were even considered. What we can confidently do is move forward with the knowledge that our gut bacteria affect our mental health, and that alone has plenty of implications for our everyday life. 

In Conclusion

Time, research, and advances in sharing our human experiences on a global and instant scale (aka, the internet) have led to a greater awareness of mental health issues. With greater visibility and acceptance of mental health struggles comes more research and health tools, and with more research and tools comes more awareness and improvement. This is an important cycle, and we are still in the very early stages of uncovering the full connection between our mental health and our microbiome. It’s exciting to consider the advancements in knowledge and interventions that could be made in our lifetime! Until then, keep learning about your body and bacteria, and know that if you struggle with mental health issues, you are not alone. 

TLDR: Gut bacteria can and does affect mental health. The most common way is via neurotransmitters that communicate from the gut to the brain. This area of study is very new!

Mental Health Resources

Psychology Today- find a therapist in your area, search by specialty, see their prices and insurance options

BetterHelp- online therapy at affordable rates

National Institute of Mental Health- detailed information and resources

Contact your city or county health office for mental health facilities and services in your area

Sources and helpful info:

Butler, M. I., Mörkl, S., Sandhu, K. V., Cryan, J. F., & Dinan, T. G. (2019). The Gut Microbiome and Mental Health: What Should We Tell Our Patients?: Le microbiote Intestinal et la Santé Mentale : que Devrions-Nous dire à nos Patients?. Canadian journal of psychiatry. Revue canadienne de psychiatrie, 64(11), 747–760. https://doi.org/10.1177/0706743719874168

Carpenter, S. (2012, September). That gut feeling. Monitor on Psychology, 43(8). http://www.apa.org/monitor/2012/09/gut-feeling

Clapp, M., Aurora, N., Herrera, L., Bhatia, M., Wilen, E., & Wakefield, S. (2017). Gut microbiota's effect on mental health: The gut-brain axis. Clinics and practice, 7(4), 987. https://doi.org/10.4081/cp.2017.987

O'Mahony, S. M., Clarke, G., Borre, Y. E., Dinan, T. G., & Cryan, J. F. (2015). Serotonin, tryptophan metabolism and the brain-gut-microbiome axis. Behavioural brain research, 277, 32–48. https://doi.org/10.1016/j.bbr.2014.07.027

Reigstad, C. S., Salmonson, C. E., Rainey, J. F., 3rd, Szurszewski, J. H., Linden, D. R., Sonnenburg, J. L., Farrugia, G., & Kashyap, P. C. (2015). Gut microbes promote colonic serotonin production through an effect of short-chain fatty acids on enterochromaffin cells. FASEB journal : official publication of the Federation of American Societies for Experimental Biology, 29(4), 1395–1403. https://doi.org/10.1096/fj.14-259598

Taylor V. H. (2019). The microbiome and mental health: Hope or hype?. Journal of psychiatry & neuroscience : JPN, 44(4), 219–222. https://doi.org/10.1503/jpn.190110