The Gut - Brain Axis is Real.
The gut microbiome plays a crucial role in neurotransmitter production, directly impacting mood, focus, and cognitive function. Certain bacterial species are responsible for synthesising key neurotransmitters, while imbalances in these microbes can lead to neurochemical disruptions associated with mental health and attention disorders. Lactobacillus and Bifidobacterium are essential for producing serotonin, the neurotransmitter that regulates mood, sleep, and emotional well-being. A decrease in these beneficial bacteria is often linked to depression and anxiety. Similarly, Escherichia, Bacillus, and Lactobacillus contribute to dopamine production, which is crucial for motivation, attention, and learning. Lower levels of these microbes have been associated with ADHD and cognition.
Additionally, Lactobacillus and Bifidobacterium are also responsible for producing gamma-aminobutyric acid (GABA), the primary inhibitory neurotransmitter that calms the nervous system and reduces stress. A deficiency in GABA-producing microbes can lead to heightened anxiety, stress, and difficulty concentrating. Conversely, an overgrowth of Bacteroides has been linked to neuroinflammation and an imbalance in glutamate-GABA signaling, contributing to hyperactivity and impaired cognitive function. Furthermore, Faecalibacterium prausnitzii and Roseburia produce short-chain fatty acids (SCFAs) like butyrate, which support brain health by reducing neuroinflammation and enhancing neuroplasticity. A decline in SCFA-producing bacteria has been observed in individuals with depression and neurodegenerative conditions.