The gut and the brain are linked through the Vagus Nerve, often referred to as 'the wanderer,' which is a component of the parasympathetic nervous system (PNS). This connection explains why individuals experiencing depression and anxiety often report gut-related symptoms like diarrhea and nausea. Perhaps you've experienced the sensation of "butterflies" in your stomach when feeling excited or nervous. This feeling results from the intricate network of nearly 500 million nerves that facilitate communication from the gut to the brain.
Both the gut and the brain are impacted by a shared neurotransmitter known as serotonin (5-HT). It's fascinating to note that nearly 90% of the serotonin in our bodies is produced in the gut wall, surpassing the levels found in the brain. This phenomenon has earned serotonin the nickname "happy hormone" due to its mood-stabilizing properties, playing a pivotal role in mental well-being and emotions.
Remarkably, several neurotransmitters crucial for mental health are either produced by gut cells or gut microorganisms. The gut takes responsibility for generating:
Research suggests a potential link between the quality of our gut bacteria and the risk of developing Alzheimer's disease, especially among individuals with a genetic predisposition to the condition. Unhealthy gut bacteria can trigger inflammation, which serves as a critical signal and contributing factor to numerous diseases, including various neurocognitive disorders.
Although our genetic makeup influences the likelihood of certain diseases, our lifestyle choices significantly influence how these conditions manifest. Epigenetic factors, such as the use of antibiotics, mode of birth (caesarean section versus vaginal birth, impacting gut bacteria colonization), exposure to toxins, and consumption of highly processed diets, can activate or suppress genetic predispositions to diseases. Epigenetics describes processes that can speed up, slow down, or reverse gene expression.
In essence, we possess more control over our health than we may realize. A healthy gut and a healthy brain are closely interconnected. The phrase "heal your gut, heal your brain" emphasizes that focusing on optimizing gut health can lead to overall well-being improvements in numerous ways.