The Gut-Brain Axis: The Connection Between Probiotics and Brain Health
The gut and the brain are two separate organs that seem to have nothing in common, however, studies have shown that there is a strong connection between the two. Specifically, the connection lies within the gut-brain axis: a complex communication network that exists between the gut and the brain.
What is the Gut-Brain Axis?
The gut-brain axis is a complex system that involves the central nervous system (CNS), the enteric nervous system (ENS), and the gut microbiota. The CNS coordinates incoming and outgoing signals to and from the brain, while the ENS is a complex network of nerves that exist within the stomach and intestine and are responsible for the regulation of digestive functions.
The gut microbiota, on the other hand, refers to the trillions of microorganisms that live within the gut. These microorganisms play an important role in a wide range of physiological processes, including digestion, metabolism, immune system function, and brain function.
The Role of Probiotics in the Gut-Brain Axis
Probiotics are live microorganisms that, when consumed in adequate amounts, confer health benefits to the host. These microorganisms are commonly found in fermented foods such as yogurt, sauerkraut, and kimchi.
Studies have shown that probiotics have a positive impact on gut microbiota diversity, which is crucial for a healthy gut microbiome. Additionally, it has been suggested that probiotics may have direct effects on brain function by modulating the gut-brain axis.
The Benefits of Probiotics for Brain Health
There is a growing body of evidence suggesting that probiotics may have a beneficial impact on brain function. Studies have shown that probiotics may improve symptoms of anxiety and depression, as well as improve cognitive function.
One study found that individuals who consumed probiotics for four weeks had reduced activity in brain areas associated with the processing of negative emotions, suggesting that probiotics may have an anxiolytic effect (1).
Another study found that probiotics may confer benefits for individuals with depression. In this study, individuals who consumed a probiotic supplement for eight weeks had significantly reduced symptoms of depression compared to the placebo group (2).
Finally, studies have shown that probiotics may have a positive impact on cognitive function. One study found that individuals who consumed probiotics for twelve weeks had improved memory performance compared to the placebo group (3).
Conclusion
The gut-brain axis is a complex system that involves the CNS, the ENS, and the gut microbiota. Probiotics are live microorganisms that have been shown to have a positive impact on the gut microbiota, and may also have direct effects on brain function.
Although more research is needed to fully understand the mechanisms by which probiotics impact the gut-brain axis, the evidence thus far suggests that probiotics may be a promising tool for the promotion of brain health.
Sources
1. Tillisch, K., Labus, J., Kilpatrick, L., Jiang, Z., Stains, J., Ebrat, B., … & Mayer, E. A. (2013). Consumption of fermented milk product with probiotic modulates brain activity. Gastroenterology, 144(7), 1394-1401.
2. Akkasheh, G., Kashani-Poor, Z., Tajabadi-Ebrahimi, M., Jafari, P., Akbari, H., Taghizadeh, M., … & Esmaillzadeh, A. (2016). Clinical and metabolic response to probiotic administration in patients with major depressive disorder: A randomized, double-blind, placebo-controlled trial. Nutrition, 32(3), 315-320.
3. Steenbergen, L., Sellaro, R., van Hemert, S., Bosch, J. A., & Colzato, L. S. (2015). A randomized controlled trial to test the effect of multispecies probiotics on cognitive reactivity to sad mood. Brain, behavior, and immunity, 48, 258-264.
