Your gut is telling your brain what to do. The best way to get into a better mood is simple: eat better food.
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Did you know that phrases like “gut wrenching emotions” and “I felt that in the pit of my stomach” are not just figures of speech? These come from very real neural signals that originate in the gut. You won’t get these neurons to compose orchestras or parse complex thoughts into words, but your belly contains a neural messaging system boasting greater processing capacity than either the peripheral nervous system or spinal cord.
For years, some scientists have been calling this enteric nervous system “the second brain” but recent studies suggest that, from a flow of information perspective, the enteric system may be even higher on the neural totem pole than the more famous, skull-based nerve center. This understanding explains why the food we eat is directly related to our mental state, our overall vitality and our susceptibility to disease.
Our digestive tract is the 30-foot-long tube through which we absorb nutrition from our food. The walls of this tube are embedded with a dense web of neurons that pass information through the vagal nerve (also known as the ‘wandering nerve’), which connects numerous organs to the brain. We like to think of our brain directing our organs, but 90% of the messages that travel along the vagal nerve move from the gut to the brain rather than the other way around. This begs the shocking question: is our gut telling our brain what to do?
In many ways, this is exactly what happens. The enteric nervous system initiates information flow in the form of hormone production, neurologic messaging and immune response.
We like to think of hormonal messaging initiating in the brain, but in fact hormonal messaging begins in many parts of the body, with much originating in the gut.
Serotonin is a neurotransmitter and hormone related to mood and more that 90% of the body’s serotonin is produced in the digestive tract. It doesn’t stop there. We’ve long suspected that the flora in the gut directly affects hormones, but a recent study by Caltech confirms the theory; mice without gut bacteria produce 60% less serotonin, and even more interestingly, adding bacteria back into these animals’ digestive tracts largely restores the serotonin production.
Want to be in a better mood? Eat better food.
The gut’s neurological reaction to dietary influences helps to explain why gluten is so detrimental to so many people. The red-hot gluten-free diet trend isn’t just a fad – it’s a very real nutrient sensitivity. Gluten guru Tom O’Bryan told me recently that he believes gluten, in people sensitive to it, behaves as a neurotoxin. This would explain symptoms of gluten intolerance that include dizziness and numbness in the hands and feet as well as neuropathy that occurs in people with gluten sensitivity who do not limit their gluten intake. Studies support O’Bryan’s theory: removing gluten from the diet reduces the symptoms of neuropathy while continued gluten consumption causes further deterioration.
Want to avoid the harsh effects of food sensitivities? Get tested for nutrient sensitivities including gluten and casein in dairy products.
The brain in the head is protected, to some degree, from environmental insults by the blood-brain barrier, provided the network of capillaries that makes up the blood brain barrier is in good condition. The brain under the belt also has a protective barrier, the endothelium of the intestines and an enormously powerful immune system; 80% of the body’s immune function is located in the gut.
When working properly, the endothelium lets in the good stuff and keeps out the bad. When the endothelium is compromised, as in the case of inflammatory bowel diseases like ulcerative colitis or nutrient sensitivities, the endothelium initiates an inflammatory, protective response in the gut’s powerful immune system that causes more harm than good. Among other things, this causes the intestines to become more permeable, allowing bacteria, partially digested food, and other unwanted elements to pass the endothelium and triggers additional inflammatory immune response as the body attempts to rid itself of the invaders.
Want to avoid being attacked by your own immune system? Keep the brain under your belt happy and healthy.
The brain under the belt is inseparable from the brain between our ears, and even our heart and vascular system has a much more active role in initiating hormonal messaging and immune response than was understood even just a few years ago. Could this brain-like activity in the gut and vascular system be the reason that data is showing the same nutrition and lifestyle risk factors for heart disease are also risk factors for dementia?
So next time somebody suggests a junk food meal, do your entire system a favor and reply, “The brain under my belt really doesn’t like that idea.”
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To learn more about this and Dr. Mark, visit menoclinic.com
Photo credit: Flickr/LydiaPintscher