Gut-Brain Axis Modulators

The gut-brain axis is the concept of a communication network, connecting the gut and the brain. Through direct signaling and molecules residing in the gut, the brain and gut affect the function of the other. For example, when people feel nervous, these feelings of anxiety from the brain are usually accompanied by nausea in the gut. Serotonin is made in the gut and communicates through nerves, resulting in feelings of happiness and peace. These are due to the gut-brain axis. Overall, this communication is very important to one’s health, and without it, people are left vulnerable to diseases and disorders.

Essentially, gut-brain axis modulators are substances that change composition within the gut-brain axis. By modulating the gut-brain axis, the risk of getting mental diseases and disorders decreases. Microorganisms and fibers have been shown to act as a modulator, decreasing the chances of disorders such as depression, Alzheimer's, and anxiety. Probiotics, an example of microorganisms, reduce inflammation in the gut and lessen feelings of sadness, too. Prebiotics, an example of dietary fibers, also improves gut health by feeding the bacteria living inside.

Changes in diet are also an example of gut-brain axis modulators. Eating healthy foods, specifically fermented foods, can improve gut health by fostering the growth of gut bacteria. In turn, the body becomes less “stressed” and less feelings of unhappiness are transmitted from the gut to the brain. 

The gut-brain axis is essential to living a happy and healthy life; without it, the digestive system wouldn’t be able to function normally, leading to an increase of sadness and depression. By using modulators, these problems can be prevented, and the brain and gut can function without issues.

References:

Ansari, Fereshteh, et al. “The Role of Probiotics and Prebiotics in Modulating of the Gut-Brain Axis.” Frontiers in Nutrition, vol. 10, 26 July 2023, https://doi.org/10.3389/fnut.2023.1173660.

Fekete, Mónika, et al. “Exploring the Influence of Gut–Brain Axis Modulation on Cognitive Health: A Comprehensive Review of Prebiotics, Probiotics, and Symbiotics.” Nutrients, vol. 16, no. 6, 1 Jan. 2024, p. 789, www.mdpi.com/2072-6643/16/6/789#:~:text=Increasing%20research%20results%20confirm%20that, https://doi.org/10.3390/nu16060789.

“Fermenting the Facts: A Science-Based Guide to Fermented Foods.” Nutrition, 2025, med.stanford.edu/nutrition/education/Resources/Fermenting-the-Facts.html.

Li, Guoli, et al. “Serotonin Signaling to Regulate Energy Metabolism:a Gut Microbiota Perspective.” Life Metabolism, vol. 4, no. 2, 23 Nov. 2024, academic.oup.com/lifemeta/article/4/2/loae039/7907792, https://doi.org/10.1093/lifemeta/loae039.

Morrill, Julia. “The Gut-Brain Axis: How Your Gut Impacts Your Mental Health.” NewYork-Presbyterian, 18 July 2025, healthmatters.nyp.org/the-gut-brain-axis-how-your-gut-impacts-your-mental-health/.

Osadchiy, Vadim, et al. “The Gut–Brain Axis and the Microbiome: Mechanisms and Clinical Implications.” Clinical Gastroenterology and Hepatology, vol. 17, no. 2, Jan. 2019, pp. 322–332, www.cghjournal.org/article/S1542-3565(18)31081-4/fulltext, https://doi.org/10.1016/j.cgh.2018.10.002.

Rajanala, Koumudhi, et al. “Modulation of Gut-Brain Axis by Probiotics: A Promising Anti-Depressant Approach.” Current Neuropharmacology, vol. 19, 15 Dec. 2020, https://doi.org/10.2174/1570159x19666201215142520.

Tompa, Rachel. “What’s the Deal with the Gut-Brain Connection?” News Center, 2025, med.stanford.edu/news/insights/2025/03/gut-brain-connection-long-covid-anxiety-parkinsons.html.

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