Your gut is talking — and your brain is listening. Discover how diet, microbiota, and even fasting reshape your brain chemistry, mood, and cognition in this deep dive into the gut-brain connection.

Your gut is talking to your brain — and your brain is listening. In this episode of The Cognitive Performer, we explore the gut-brain axis — the communication highway connecting your digestive system and your mind. Discover how trillions of microorganisms influence your mood, focus, memory, and long-term brain health. We’ll look at how diet shapes your microbiome, why certain bacteria can act like microscopic pharmacists, and what dietary patterns best protect cognitive function. From the serotonin-shaping power of Roseburia intestinalis to the fasting-linked boost in microglial cleanup, this episode unpacks the real neuroscience behind “gut feelings.”

• Roughly 90 % of the vagus-nerve signals run from gut → brain, not the other way around.
• The gut microbiome produces neurotransmitters such as serotonin, dopamine, and GABA that directly influence mood and cognition.
• Stress diverts tryptophan from serotonin production toward inflammation — but beneficial bacteria can reverse that shift.
• Mediterranean, DASH, and MIND diets consistently support brain health by nourishing diverse gut bacteria.
• Alternate-day fasting reshapes gut microbes and improves microglial function, translating into measurable cognitive gains.
• Building cognitive reserve through learning, social connection, movement, and sleep can cut dementia risk nearly in half.

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