Author: Dr. Bonnie Brock, NMD, RD, MPH
Anxiety or depression is much more than an inconvenience as it can greatly impact your health; lowering your immunity, increasing cancer and other disease risk and even contributing to pain. New research shows that mood issues are more than neurotransmitter imbalances but can be rooted in the gut microbiome. I noticed the connection between gut health and brain health way back in the early 90s, while working as a dietetic intern in the hospital. Back then, each patient had an enormous paper chart, with every aspect of their health and hospital journey documented. In order to learn, I would spend hours, sitting at the nurse’s station and reading through all the chart notes on every patient. As an intern, I transitioned through each department of the hospital; diabetes, renal, oncology, gastro, etc.. I remember reading through pharmacology notes to become familiar with each medication type and its function. I learned all about insulin, and statins and diuretics, etc. I noticed that each patient in each department was on similar medications (makes sense). But when I got to the gastroenterology department, each patient was usually on some sort of antibiotic or motility or ant-diarrhea agent, but also on an anti-depressant or anxiety medication. I remember asking the residents why each patient in gastroenterology was also seemingly on a mood medication, and why that didn’t seem to be the case in other hospital departments. Back then, I never got a good explanation from the residents, but now I understand it has to do with the connection between the state of the mind and the health of the gut. And even today, most psychiatric medications are limited by only manipulating neurotransmitters, but imagine if you could address mood issues with diet and gut health.
The gut microbiome contains 100 trillion microorganisms that influence our wellbeing in significant ways. The balance of beneficial to pathogenic organisms in the gut is of utmost importance, and when this balance is thrown off it is called dysbiosis. Most chronic diseases are associated with dysbiosis at some level.
You may be wondering how the community or microorganisms housed way down in the large intestine can impact the brain and mood. We are starting to understand that there is a direct connection between the brain and gut, called the gut-brain axis and there is constant communication between the two organs. Bidirectional information flows between the gut and brain along cranial nerve 10, the vagus nerve. The vagus nerve is so named because it resembles a “vagabond”, traveling down from the brain, communing with the heart and lungs, twisting itself all throughout the intestines and picking up and sending information all along the way. The microbiome sends messages to the brain, through the use of neurotransmitters, hormones, proteins, and other communication factors.
Food poisoning is an excellent example of gut-brain communication. Pathogenic bacteria are coated with something called lipopolysaccharide, or LPS, and you have sensors in the gut to measure LPS levels. If LPS levels get too high, as in a gut infection or a bout of food poisoning, the nerves send a message up to the brain that conditions are unfavorable, and intervention is needed. The brain then signals a series of events to induce vomiting, stomach cramping, nausea and diarrhea, in order to prevent you from eating more of and removing the contaminated food. This is an example of gut to brain to gut communication in order to protect you and keep you well.
But do the microbes in the gut influence how you feel, your emotions, and your happiness in a very real and tangible way? The answer is yes, they do, and it starts with the autonomic nervous system. The autonomic nervous system (ANS) runs thousands of automatic, involuntary functions which are constantly running in the background of our bodies.
Your autonomic nervous system has two parts:
- Sympathetic nervous system (SNS) – Your sympathetic nervous system is primarily responsible for your fight-or-flight reactions. The SNS is vital to your survival and ramps up when needed – the problem in today’s world, the SNS tends to stay in hyper-drive due to things like politics, stress at work, and even triggers from social media.
- Parasympathetic nervous system (PNS) – Your parasympathetic nervous system influences repair systems throughout the body. The PNS is associated with “rest-and-digest” and feelings of connection, love, and friendship. Your PNS works to counterbalance the SNS.
Then there is your enteric nervous system (ENS), which is a massive mesh-like network of neurons that is embedded in the wall of your gastrointestinal tract. Your enteric nervous system receives signals from both your sympathetic and parasympathetic nervous system. This is important because your ENS should be receiving and giving signals from both the sympathetic and parasympathetic evenly – symmetrical signals keep you feeling balanced. When one dominates, the sympathetic for example, you can feel stuck in “fight-or-flight” feelings.
Your ENS communicates with your central nervous system via the vagus nerve. Remember, vour vagus nerve is the direct line of communication between your gut microbiome and your brain. Believe it or not, the ENS is responsible for creating and moving neurotransmitters, with about 95 percent of serotonin being produced by nerves and microbes in the gut. This serotonin, plus dopamine, and glutamate, influence various body functions, including digestion, immunity and of course, mood. In fact, your ENS has been labeled “your second brain” because of its power over your emotions. The lines between the gut and the brain are more blurred than we’ve ever realized before.
Your gut microbiome can contribute to anxiety and depression in a number of ways. As we saw with our food poisoning example, the make-up of the microbiome can influence your brain’s autonomic stress response. The microbiome can also cause changes in your gut border permeability or cause “leaky gut”. Leaky gut is when the cells lining your gut aren’t stuck together as tightly as they could be, allowing proteins, viruses, bacteria, and more to leak out of the gastrointestinal tract and into the bloodstream. As you can imagine, the movement of these unwanted items into the bloodstream triggers an immune response and “sounds the alarm” in the brain, causing anxiety and other improper emotional responses. Dysbiosis can also cause chronic inflammation and the release of stress signals, which leads to increased anxiety and depression through the gut-brain communication system.
Can you imagine a future where anxiety and depression is treated through the gut? Perhaps the most important takeaway from this revolutionary information is that the gut microbiome influences our brain at least as much as the brain influences the gut – if not more. Your gut microbiome is as unique to you as your fingerprint, and is dynamic and constantly changing. The trillions of microorganisms living in your gut include bacteria, viruses, yeast, parasites, fungi, bacteriophages and more. In the most simple terms, we know it’s important to boost beneficial microbes while decreasing the harmful ones. It is important to understand the contents of your specific microbiome through functional testing with a qualified practitioner. Here at Acacia, we offer a 3-collection stool analysis with a 16-page report on every aspect of your microbiome and its indications for better health. Contact Dr Bonnie Brock at Acacia Natural Medicine for questions and to schedule your microbiome analysis.
