The connection between the brain and the gut is profound.
Your gut microbiome is a highly intelligent ecosystem of organisms. Bacteria tend to dominate this ecosystem, but you’ve also got viruses, fungi, and protozoan, among other organisms that exist there. Your microbiome is defined as all of these organisms, including their genetic elements.
When the bi-directional connection between the brain and the gut (also called the gut-brain axis) is underdeveloped, and/or the ecosystem becomes imbalanced, we often see anxiety, depression, violent behavior, autoimmunity, ADHD, eating disorders, autism, and a lot of other conditions I work with in my clinic.
There are actually a few reasons the gut is called the second brain. First, a lot of metabolic and neurotransmitter byproducts such as serotonin, dopamine, and GABA are produced in the gut that affect the brain in a very significant way. The second reason is that the enteric nervous system, which is a neurological system, lines the entire digestive track.
The enteric nervous system is only second to the brain in terms of the number of nerve endings it has. In fact, it’s got more nerve endings than the spinal cord does making it a very, very dense neurological tissue. The gut and the gut bacteria have direct access to the entire nervous system, and the enteric nervous system is directly connected to the brain through the vagus nerve, also called the wandering nerve because it wanders from the brain into organs in the neck, chest, and abdomen.
The vagus nerve functions in a wide variety of ways including communication between the brain and the gut, digestive tract, respiration, and heart rate functioning, speech and taste sensation, as well as fear management (fight, flight, freeze), among other functions.
If there is dysfunction of the development of the neuronal tissue itself, meaning there is not proper signaling back and forth between the gut and the brain, the effects can be profound from behavioral disorders, to memory and response time issues, as well as challenges with appetite, mood, and sleep.
However, most of the time what goes wrong is the wrong type of microbes start inhabiting the gut at high levels, therefore impacting the brain significantly. For example, if opportunistic and pathogenic microbes are allowed to proliferate, they will produce neurotransmitters in the gut that go to the brain that can cause you to have high anxiety, which can then lead to a panic disorder.
In my adolescent clients, this manifests as anxiety through tantrums, hyperactivity, and extreme meltdowns over the slightest little occurrence. Often these episodes occur after consumption of sugary processed foods loaded with gluten, dairy byproducts, and lots of chemical flavorings engineered in a lab designed to stimulate opioid receptors (thus creating a “high”) in the brain. These foods are triggers because they feed the “bad” microbes into producing the aforementioned byproducts that are inflammatory to the brain (and body, as we often see in autoimmune disorders such as Hashimoto’s thyroiditis).
As adults, we have learned over time how to navigate the world by suppressing our anxiety. Unfortunately, this causes us to socially isolate, binge on food and alcohol, and live in fear, afraid to reach out for help. I spent most of my life this way so I have an intimate understanding here.
I am often asked how did I get a leaky gut or why do I have SIBO (small intestinal bacterial overgrowth) or yeast overgrowth? The answer is simple, yet layered: genetics is one piece (including biochemical imbalances from mom and dad), epigenetics (how your genes interact with your environment) yet another. When you layer in stress from work and relationships, heavy antibiotics in childhood on top of a standard American diet (or very restrictive dieting), a shift in the microbial terrain occurs creating permeability issues to the gut barrier.
You have a magnificent intelligence that resides in your gut. Gut reconditioning, nutrient and dietary therapy, as well as lifestyle modifications are powerful in their ability to heal the gut, creating health and happiness in your life.

Gut Inflammation Articles
How Gut Inflammation Causes Anxiety
What to Do When Diet and Probiotics Don’t Work
Could Oxalate Toxicity Be the Cause of Your Health Issues?
Glutamine Versus Glutamate: Nutrients and Safety
Ashwagandha: Herbal Remedy with Dangerous Repercussions
Histamine Intolerance: Methylation, the Gut, & Copper
Yeast Overgrowth and Yeast Toxicity Tips
Gluten Intolerance or Oxidative Stress?
What is Breast Implant Illness?
What is PCOS and How to Reverse It

Gut Inflammation Podcast Episodes
Bonus Replay: The Gut-Brain Connection with Kiran Krishnan
EP 56: The Gut and Gum Disease Connection with Dr. Al Danenberg
EP 55: What Your Doctor May Not Know About Thyroid Function With Jim Paoletti, BS Pharmacy, FAARFM, FIACP
EP 54: Reversing Hashimoto’s and Autoimmune Diseases with Donna Mazzola, PharmD
EP 52: What Is The Main Cause of PCOS? with Dr. Felice Gersh
EP 50: Back to Basics: What is Food?
EP 46: How Oxalate Toxicity Impacts Your Health with Sally K. Norton, MPH
EP 44: How Short Chain Fatty Acids Can Fix Your Gut with Steven Wright
EP 43: How to Fix Your Gut When Probiotics Stop Working with Steven Wright
EP 41: Environmental Toxins and Your Health with Lara Adler
EP 38: The Truth About Gluten-Free Diets Part 2: The Gut Brain Connection with Dr. Tom O'Bryan
EP 37: The Truth About Gluten-Free Diets Part 1: Grainflammation with Dr. Peter Osborne
EP 33: Autoimmune Disease And The Gut Microbiome With Kiran Krishnan
EP 30: Post-Birth Control Syndrome: Fix Your Hormone and Digestive Health with Jenna Longoria, FDN-P
EP 29: Mast Cell Activation Syndrome and Histamine Intolerance with Beth O’Hara, FND
EP 28: 2 Causes of Unexplained Behavior Change in Kids with Dr. Jill Crista
EP 17: Understanding the Human Microbiome with Kiran Krishnan
“I started working with Sami because of chronic digestive issues (and I was hoping that along the way I would lose about 30 pounds). Now, six months later, I am 33 pounds lighter and the problems I have suffered with for DECADES are significantly better! Amazing healing has occurred! I learned so much about what diet works for my system, and with Sami’s encouragement, I have developed really good habits that I know I will stick to because I feel so good!”
NOLA WOOD, OWNER, WOOD, WIND & WATER