How does our gut signal our brain?


The communication between the gut and the brain, known as gut-brain signaling, occurs through both chemical and mechanical pathways. Here are the key mechanisms:

  1. Chemical Signaling:

    • Neuropod cells in the gut detect nutrients such as sugars, fatty acids, and amino acids. These cells then use electrical activity (action potentials) to signal the brain, leading to the release of chemicals like dopamine in the brain. This process enhances our drive for certain foods and affects our eating behavior by increasing motivation, craving, and pursuit 1.
    • Hormones such as neuropeptide Y, CCK (cholecystokinin), and ghrelin also play a role in this chemical communication, influencing our eating behaviors and satiety 2.
  2. Mechanical Signaling:

    • The gut can send signals to the brain through mechanosensors that detect the physical stretching or distension of the gut. This can suppress further eating or, under extreme conditions, trigger vomiting through the activation of the brain's vomit center (chemoreceptor trigger zone) 2.
  3. Indirect Signaling:

    • In addition to direct neural pathways between the gut and the brain, the gut microbiota can influence the brain indirectly by synthesizing neurotransmitters or other chemical messengers that travel through the bloodstream. This establishes a systemic effect that can impact mood, behavior, and general well-being 3.

      Gut-Brain Signaling

      Andrew explains how neuropod cells signal to the brain about the presence of sweet, amino acid rich, or fatty acid rich foods, causing us to seek out more of those foods. This is done by adjusting the release of neuromodulators, such as dopamine, which impacts motivation, craving, and pursuit.

      Huberman Lab

      How to Enhance Your Gut Microbiome for Brain & Overall Health | Huberman Lab Podcast #61

Through these mechanisms, the gut significantly influences our overall health, mood, and behavior, acting as a complex and dynamic system interfacing with our nervous system.