The Gut-Brain Connection


The gut, which is often referred to as the second brain, communicates with our actual brain to regulate our mental and physical wellbeing. 

Although stress and anxiety are psychological conditions, gastrointestinal problems can create stress and anxiety, but stress and anxiety can also cause gut issues.

Most of us know about the central nervous system, which is made up of the brain and spinal cord and is involved in nerve transmission between the brain and the organs. There is also a nervous system in the digestive tract, and it is called the enteric nervous system. Its network of nerves, neurotransmitters, and neurons extends from the esophagus, through the stomach and intestines, to the anus, covering the entire digestive tract to enable the gut and the brain to communicate.

Feelings and emotions can cause us to feel certain physical sensations in our digestive tracts. Nausea, butterflies, and feeling punched in the stomach are all examples of emotional impacts on the gut.

Pain and other bowel symptoms can have as much to do with emotional stress as they can have to do with physical ailments. Psychosocial factors, like stress, fear, anxiety, can influence the gut physiology and people who struggle with digestive disorders can perceive pain more acutely due to heightened pain signals from the gut. Likewise, heartburn, diarrhea, and stomach cramps can be related to stress.

Chronic stress causes us to function in fight or flight mode, which slows our digestive processes and can trigger inflammation causing irritable bowel symptoms, discomfort, stomach ulcers, and reflux.

Without sufficient good bacteria in the gut, our brains cannot process information adequately and our cognition and mood are negatively affected.

Several neurotransmitters are produced in the digestive tract. Healthy gut microbes produce brain chemicals such as GABA, serotonin, and dopamine, but they need to be synthesized in the brain from precursors which are derived from our diets. A healthy diet, with varied amino acids, is essential to provide the nutrients necessary to make the neurotransmitters.

More than 50% of our dopamine and nearly 90% of our serotonin is produced in the gut. Dopamine influences the secretion of gastric acid, gut motility, and blood flow in the mucosal lining. Serotonin imbalances result in several mental health disorders including depression and anxiety.

Dietary and environmental changes can influence the health of the gut microbes as well as the production of our neurotransmitters which is why the foods we choose to eat and the places we spend the most time can influence our physical and mental health. A high-fat diet can alter the microbes in the digestive tract resulting in inflammation in the gut, which translates to inflammation in the brain. The same is true with the overconsumption of sugars and refined carbohydrates.

Listen to my interview with Brad Kirsten from Radio Cape Pulpit on 8 December 2022 to learn more. Listen to my next interview on Thursday at 7.45am