Ever heard the phrase “second brain”? Did you know it pertains to our gut? There is a network of neurons lining the digestive tract that is so extensive some scientists have nicknamed it the “second brain” with the power to influence both mood and well-being, giving a whole new meaning to the phrase “follow your gut”. This second brain contains some 100 million neurons, more than in either the spinal cord or the peripheral nervous system! This can start to make more sense when you consider the fact that our gut measures about 30 feet in length, much much longer than the average spine.
The digestive system is equipped to work completely independent from the brain, powered with its own reflexes and senses to control gut behavior. We likely evolved this intricate network of nerves to perform digestion and excretion directly “on site,” rather than remotely from our brains through the middleman of the spinal cord. This is why our digestion still continues to do its job even after spinal cord injuries.
The gut is also home to trillions of bacteria, most of which are working very hard to support health on many different levels. When considering the number of cells in the body, we are only 10% human! The other 90% is called our microbiome, and is made up of all the microbes living in and on the body. The beneficial bacteria in the microbiome—called probiotics—work with our own bodily systems to help optimize blood sugar levels, support immune system, and even regulate moods by influencing hormone levels.
How hormones affect gut health
The body’s endocrine system produces more than 50 different hormones, many of which have a major impact on health and wellbeing. The gut, along with the bacteria within, can influence hormones to benefit health in a variety of important ways. Although serotonin (the ‘happy’ hormone) is well known as a brain neurotransmitter, it is estimated that more than 90 percent of the body’s serotonin is made in the digestive tract, leading to further studies into how greatly this can affect conditions such as anxiety and depression. Serotonin is also the building block for melatonin, a hormone that plays a major role in sleep. Well, there is 400 times more melatonin found in the gut than in the pineal gland (the part of the brain that makes the melatonin).
You may need to look to your gut for the answer. In addition, levels of estrogen in the body are affected by digestion. A normal bowel transit time allows excess estrogen to pass out of the body, rather than be reabsorbed. By optimizing digestion, probiotics help keep excess estrogen out of circulation. Lactobacillus acidophilus bacteria can also decrease activity of Beta-glucuronidase, an enzyme that enables estrogen to be reabsorbed back into the blood stream. From what we know so far, chronic irritation and inflammation in the gut can lead to various hormone imbalances and immune deficiencies, but it doesn’t stop there.
Chronic gut inflammation
Chronic inflammation in the gut can lead to the formation of larger gaps in the intestinal lining, allowing for larger food particles and other foreign substances to pass through that shouldn’t be allowed to. This is what’s referred to as ‘Leaky Gut’. Do you experience frequent bloating or abdominal discomfort? Eczema? Headaches or migraines? These are just a few of the possible signs of food sensitivities, which can be a consequence of ‘Leaky Gut’. More severe conditions such as IBS (irritable bowel syndrome) and IBD (inflammatory bowel disease; i.e. Crohn’s and Ulcerative Colitis) can also develop from chronic irritation and inflammation in the gut, and most individuals with these conditions are unaware of the major role their diet is playing in their symptoms.
The immune system and gut health
Last but certainly not least, what about our immune system? About 80% of your entire immune system lives in your GI (gastrointestinal) tract! Much of which is contributed to by gut bacteria. So, if you seem to be prone to frequent colds or infections, take a look at any digestive discomfort you may be experiencing on a regular basis. Acid reflux? Bloating? Diarrhea or constipation? All are signs that your gut isn’t happy and likely retaining a lot of inflammation. Just a little food for thought.
About Dr. Auerbach
Stephanie Auerbach, a native Oregonian and Naturopathic doctor, treats the body as a cohesive system with the inherent ability to heal itself. Dr. Auerbach emphasizes working with patients to address any immediate symptoms while also evaluating the underlying causes of each health complaint.