Redwood Naturopathic Medicine
The Gut-Brain Connection
What is the Gut-brain Connection?
Have you ever felt "butterflies" when you are nervous? Or have you ever had a "gut-wrenching" experience? The GI tract is sensitive to emotions, and emotions can trigger symptoms in the gut. The gut-brain axis is the bidirectional communication network that works between your gut and brain. This communication between the central nervous system and the enteric nervous system connects cognitive behavior with peripheral intestinal functioning. Meaning your mental/emotional health affects your ability to digest properly, and your ability to digest affects your mental/emotional health.
Since it contains the same tissue and can generate many of the same chemical messengers as the brain, the gut is known as the second brain. The enteric nervous system lines your digestive tracts with a network of neurons. Many of the same neurotransmitter communication molecules found in the brain are also found in the gut. Serotonin, the body's feel-good chemical, is present in the bowels in amounts ranging from 85 to 95 percent.
Since the stomach and intestines are directly affected by the brain, the mere idea of feeding, for example, will cause the stomach's juices to be released before the food arrives. This relationship is reciprocal. An agitated intestine can transmit messages to the brain, just like an agitated brain can do the same. As a result, stomach or intestinal discomfort may be the result or cause of anxiety, stress, or depression. Since the brain and the gastrointestinal (GI) system are intertwined, this is the case. This is particularly true when a person's gastrointestinal upset is caused by anything other than a physical trigger. It's difficult to heal a disturbed gut without understanding the role of stress and emotion in such functional GI disorders.
There are two main ways the gut and the brain stay connected. The first being the vagus nerve, which provides a direct connection to the brain. The vagus nerve controls what messages go to the gut, as well as other vital organs. The second way the brain and gut connect is through chemicals such as hormones and neurotransmitters. The chemical messages passed back and forth are subject to being affected by the bacteria and fungi that live in the gut. This is known as the gut microbiome; some species are beneficial and essential to the GI system's proper functioning. However, some species are not beneficial and cause harm. When there is an overgrowth of harmful bacteria/fungi or excessive inflammation, symptoms such as anxiety, depression, and other mental disorders become more apparent. This is happening because the harmful bacteria begin to interfere with the chemical messages being passed between the gut and the brain.
How to Improve Gut-Brain Connection?
Maintaining a strong balance in favor of beneficial bacteria in your digestive tract is critical for maintaining or restoring your microbiota's health and supporting good overall health. The first move is to eat a well-balanced diet that includes foods that contain probiotic or prebiotic ingredients, which promote microbial health by assisting in the restoration of gut microbiome balance. Some foods contain live beneficial (probiotic) bacteria and, in the case of prebiotics, substances that promote probiotic bacteria's growth, such as various forms of fiber. A GI system rich and diverse in bacteria is key to optimal health. The 38 trillion bacteria that live in our gut work to keep our bodily systems, especially the immune system, running efficiently.
Foods that help the Gut-Brain Axis:
Omega 3 Fatty Acids: A recent study at the University of Nottingham suggests that omega 3's can improve the gut's biodiversity and increase the number of healthy bacteria species in the gut. Good sources of omega 3 fatty acids are avocado, salmon, nuts, seeds, extra virgin olive oil, and coconut oils.
Fermented Foods: Fermented foods contain naturally occurring bacteria that are beneficial to the gut. These are essential to the health of our gut. Good sources of fermented foods are sauerkraut, yogurt, kefir, fermented vegetables, and cheese (if tolerated). Probiotics are also a great source of beneficial bacteria and can be supplemented daily.
High Fiber Foods: Fiber feeds the microbiome. It serves as a prebiotic, increasing the number of beneficial bacteria, which love to consume for fuel, supporting and strengthening the intestine lining and immune system. Good sources of fiber are whole grains, whole fruits/vegetables, nuts, and seeds.
Polyphenol Rich Foods: Up to 95% of the polyphenols you eat make their way to your colon undigested. It's becoming more evident that polyphenols, once broken down, play a role in gut health by modulating gut microbial balance. Dietary polyphenols stimulate the growth of beneficial bacteria while inhibiting opportunistic bacteria's growth in exchange for being converted into bioavailable metabolites. Good sources of polyphenols are green tea, cacao, berries, legumes, olive oil, and turmeric.
Ochoa-Repáraz, J., & Kasper, L. H. (2016). The Second Brain: Is the Gut Microbiota a Link Between Obesity and Central Nervous System Disorders?. Current obesity reports, 5(1), 51–64. https://doi.org/10.1007/s13679-016-0191-1
Carabotti, M., Scirocco, A., Maselli, M. A., & Severi, C. (2015). The gut-brain axis: interactions between enteric microbiota, central and enteric nervous systems. Annals of gastroenterology, 28(2), 203–209.