How gut bacteria shape our emotional landscape

Chase the blues with microorganisms

Is it possible for gut microorganisms to impact your mood? Animals and humans have provided strong evidence for this incredible theory. So let’s take a journey into the fascinating world of the gut-brain axis.

Picture this… Deep within your gut resides a bustling community of microbes, collectively known as the gut microbiota. These tiny inhabitants may seem inconsequential, but they wield incredible influence over our mental landscape.

Gut-brain interaction. The gut-brain axis represents a complex communication network between the gastrointestinal tract and the brain, influencing various aspects of human health in unexpected ways, including mood and behavior. At the heart of this intricate connection lies the gut microbiota, a community of microorganisms residing in the gut.

How the gut and the brain communicate?

  • The gut microbiota plays a pivotal role in regulating the gut-brain axis, primarily through the production of neurotransmitters, immune molecules, and metabolites that can influence neural function and behavior. One of the key ways in which bacteria exert these functions is through the production of neurotransmitters such as serotonin, dopamine, and gamma-aminobutyric acid (GABA). These neurotransmitters are not only crucial for regulating mood but also play a role in cognition, stress, and emotional well-being.
  • Moreover, the gut microbiota can modulate the immune system, affecting inflammation levels in the human body. By regulating inflammation, gut bacteria indirectly influence mood and behavior. Chronic inflammation has been linked to various psychiatric disorders, including depression and anxiety.
  • Furthermore, the gut microbiota interacts with the vagus nerve, a major bidirectional communication pathway between the gut and the brain. This interaction allows signals generated in the gut to be transmitted to the brain, influencing mood, stress, and even cognitive function. Additionally, the gut microbiota can produce short-chain fatty acids (SCFAs), messengers having neuroactive properties.

Keep a healthy gut microbiota. The composition of the gut microbiota is influenced by various factors, including diet, stress, antibiotics, lifestyle, and environmental exposures. The dysbiosis of the gut microbiota, a state of microbial imbalance, have been associated with an increased risk of mood disorders, such as depression and anxiety.

In summary… The gut-brain axis represents a dynamic and intricate communication system that plays a crucial role in modulating human mood and behavior. Understanding the intricate interplay between the gut microbiota and the brain may offer novel approaches for the treatment and management of mood disorders, starting from specific probiotic supplementation.


Valles-Colomer, M., Falony, G., Darzi, Y., Tigchelaar, E. F., Wang, J., Tito, R. Y., … & Raes, J. (2019). The neuroactive potential of the human gut microbiota in quality of life and depression. Nature Microbiology, 4(4), 623-632.

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    Diletta Francesca Squarzanti


    R&D Specialist

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