The 3 Amigos: The Gut Brain Connection

By Edison de Mello, MD, PhD

Yes, we have 3 Brains! The first one is the HEAD, then the HEART, followed by the GUT brain. These 3 brains are interconnected through an extensive network of neurons, each with particular roles. Resembling a highway of information, these brains, when balanced, provide stability, grounding and the intuition (gut feelings) necessary for ultimate health.

Containing about 100 million neurons, the gut-brain works both independently and in conjunction with the head and the heart brain. Research has shown that gut bacteria, also known as the microbiota, directly communicate with the head brain playing a crucial role in mood, memory cognition, and satiation. Anxiety and depression, for example, are conditions known to contribute to gastrointestinal conditions, such as irritable bowel syndrome (IBS), small intestinal bacterial overgrowth (SIBO), and Leaky Gut, among others. All of which have bloating as a common denominator.

The gut feeling (intuition) or “butterflies” in the stomach that are often a result of having to make a decision about some important things, is actually a physiological response secondary to getting signals from our head, to our second brain, that is, our gut. Studies identifying this “little brain hidden in our gut” has revolutionized our understanding of the link between overall health, digestion, and elimination.

But why do we have 3 brains and how do they relate to one another?

Your gut is your second brain. But If our brain is the first brain and our gut is the second brain, which one is the main brain? AND HOW ARE THEY CONNECTED?

The answer is, they are all very interconnected. In fact, this connection goes all the way back to the beginning of life, when we were nothing but a group of small cells in our mother’s womb. The Enteric Nervous System (or ENS) , being that it was the first system to develop and that it hardwired itself into our gut, plays a very important role in transmitting information back and forth between the main Head brain and the Gut brain that controls secretions and blood flow, allowing us to efficiently digest and absorb our food. This significant and complex relationship between the head brain and the ENS is referred to in scientific papers as the Gut-Brain Axis. An impressive body of research has delineated the vital influence that the microbiome plays on our emotional state. All via the Gut-Brain Axis. It has been proven that changes in the gut microbiome due to chronic inflammation, stress, antibiotics, high carbohydrate diet, high sugar intake, or high toxic load from food and environment has a tremendous negative impact on our three brains.

As such, chronic inflammation, a natural response from the immune system to a threat, injury, or invader can lead to bloating, IBS – or leaky gut, a condition in which the lining the gut, more specifically the pores, become inflamed and swollen. This, in turn, allows the pores to expand. The expansion of the pores lets unfiltered and undigested large substances pass through the bloodstream creating auto-immune inflammatory conditions and other inflammatory responses leading to havoc in the body. When Inflammation becomes chronic, it starts a domino-effect of damage to the entire system. Chronic inflammation is now known to be the leading cause of many chronic diseases we face today, including bloating, heart disease, and even cancer.

Their Distinct and Combined Role:

1. The Head Brain analyses and applies logic.

2. The Heart Brain senses the world emotions and feelings.

3. By helping us understand our identity and who we are in the world, the Gut Brain. teaches us self-preservation by directing us to follow our instinct, the “gut feeling” we all have the ability to experience.

Chronic inflammation and the 3 brains:

Bloating, brain fog, headaches, anxiety, fatigue, and decreased cognition are caused by antibodies that compromise the blood-brain barrier leading to the leaking of toxins directly into the blood stream that causes, for example, Leaky Gut Syndrome. This allows harmful substances to cross directly into the system thus creating dangerous inflammatory conditions.

Inflammation in the gut also significantly affects the production of neurotransmitters. With 90% of serotonin – the happy hormone – being metabolized and stored in the gut, the magnitude of the critical functions of the gut is astounding. In addition, the gut is also home to dopamine, glutamate, norepinephrine, GABA, and nitric oxide. Together, these neurotransmitters are fundamentally important to our vitality and well-being, including brain performance.

How do the Three Brains Communicate with each other?

The main link of our 3 brain connection is via the Vagus Nerve, often referred to as the ‘Wandering Nerve” because it’s the only cranial nerve that exits the skull and continues down past your neck into the gut, creating what is now known as the Brain-Gut Axis. A vital key component of the 3 amigos connection, the vagus nerve links the enteric nervous system to both the Head and the Gut brains.

Our three brains don’t always align. They Sometimes Conflict

You, like most people, have probably experienced conflicts between your 3 brains. Something like, your brain points you in one direction but your heart and/or gut says the opposite. Or perhaps you’ve had that familiar, yet annoying sense that something is off but your brain keeps looking for the “it” that is off only to find nothing to confirm your suspicion. And yet you’re still not convinced that something is not off? Health issues also follow the same pattern and perpetuate if we fail to understand the three brains.

What is the function of the Gut’s Brain?

From swallowing to releasing enzymes whose function is to break down food, optimizing blood flow to facilitating nutrient absorption and elimination, the role of the Gut-Brain in digestion is like no other. The back and forth open the line of communication between the Gut Brain (enteric nervous system) and the big brain (Aka Head Brain) has a strong influence in everything the body needs to do to operate effectively, in addition to the essential functions of digestion and elimination.

Because the ENS directly influences the mood of those dealing with bloating, constipation, diarrhea and a host of other GI-related conditions, doctors and researchers attribute emotional states such as anxiety and depression as significant contributing factors. This is one of the reasons why, for example, patients with bloating due to IBS, SIBO, and other bowel-disorders usually respond well to mood enhancing herbal remedies, and in some cases, to traditional antidepressant treatments and mind-body therapies such as cognitive behavioral therapy or (CBT), meditation, yoga, tai chi, and medical hypnotherapy to name a few. In essence, primary-care and GI doctors treating people with gut related conditions often, like a psychotherapist, find themselves “soothing the second brain.” In other words, emotional interventions are used to improve communication between the head brain (big brain), and the gut brain (little brain) residing in the gut; thus it must be a major component of any treatment aimed at eliminating gut inflammation.

Dr. Edison de Mello is the Founder and Chief Medical Officer at the Akasha Center for Integrative Medicine. If you would like to schedule an appointment please call 310-451-8880 or email us at info@akashacenter.com.

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