Our Microbiome – The “Gut-Brain Axis”

bookHave you ever experienced butterflies in your stomach? An undeniable “gut instinct” or “gut feeling”?

There’s a reason these sayings have come to be and that is the rising scientific recognition that there lies a connection and interplay between our brain, our thoughts our feelings and our gut physiology – the “Gut-Brain Axis”.  The idea that the gut, can not only affect us physiologically, but can affect the mind, as neuroimmunologist John Bienenstock (MD of McMaster University in Hamilton, Ontario) states, “has just catapulted onto the scene”.  OR has it? Just over 200 years ago, Hippocrates stated the all famous quote…

“All disease begins in the gut”.

Recent studies have now proven that the human gut contains what they’ve coined as our “second brain”, which is housed under the mucosal lining and between the muscular layers of the esophagus, the stomach and the small and large intestines. Our second brain or the Enteric Nervous System (ENS) within our gut, contains a complex network of neurons and neurochemicals that are able to sense and control events in other parts of the body, including our brains. In fact the number of nerve cells in the second “gut” brain, is significantly greater than the number of nerve cells in the spinal cord! What connects these responses is a communication from the brain to the gut and vice versa, through what is known as the Vagus Nerve, which within our gut is surrounded by a host of over 100 trillion microorganisms and bacteria, collectively referred to as the microbiome. This microbiome of flourishing bacteria, influence neural development, brain chemistry and wide range of behavioral responses, such as emotional behavior, pain perception and how our stress response system functions. So sophisticated is this neural network of bacteria, that it can continue to perform its functions even if the Vagus Nerve is severed!

More reasons why our gut bacteria so essential to how we are thinking and feeling emotionally and physiologically:

  • Gut bacteria produce HUNDREDS of neurochemicals that the brain is able to use to regulate physiological and mental processes such as memory, mood and learning.
  • The gut produces 92-95% of the body’s supply of serotonin! Which is our happy neurotransmitter that many who are experiencing mental health imbalances such as depression are lacking.
  • Gut bacteria regulates digestion and metabolism, which then assists in absorption of the cofactor nutrients that are essential to build neurotransmitters, hormones and perform cellular reproduction.
  • They extract and also make vitamins and nutrients from the food that we eat
  • The gut hosts 80% of our immune system and help to program it.
  • Bacteria in the gut builds and maintains the gut wall, protecting the body from outside invaders, pathogens and toxins that can invade the blood stream to the brain affecting our cognition, behaviour and emotions.

It works both ways…

Briefly stated, if we are stressed, our body’s go into what is known as “fight or flight”, which draws our blood flow away from our digestive system to our extremities, our muscles, our heart etc., in order to survive a state to which the body is identifying as a threat. Consequently, this impairs the breakdown of our food, causing digestive distress which results in undigested food entering the intestinal system and thus compromising our healthy microbiome of bacteria. Poorly digested sugars from carbohydrates for instance (the dissacharides) will eventually cause bad bacteria and pathogens to begin to produce and flourish taking over good bacteria and causing a host of symptoms, which I’ll save for another post! Ultimately, we must consider how we can make stress management a priority in our lives as it directly affects our gut health, which we now know has a direct effect on our brain and mental health!


Do you or someone you know suffer from a high stress lifestyle, Irritable Bowel Syndrome (IBS), Crohn’s Disease, Anxiety, Depression, Schizophrenia, Bi Polar, Eating Disorders, Addictions, ADD/ADHD or Autism Spectrum Disorder? They may be experiencing an underlying compromised microbiome and gut health that can be supported and rebalanced.

Although seeking a holistic nutritionist for a diet plan tailored to your individual and unique biochemical makeup can be greatly beneficial for supporting your journey to improved physical and mental health, here are some important steps you can take to protect and flourish your good bacteria and support gut health for improved mental health:

  • Taking a good quality probiotic.
  • Consume more natural probiotics including fermented foods such as fermented coconut, sauerkraut or kombucha.
  • Juice raw cabbage! This has a natural source of L-glutamine which is a nutrient essential for healing the mucosal lining of the intestine.
  • Eat clean! What does this mean? That means eating foods that are whole, live, natural, from the earth and in season, ideally organic. Plants Plants Plants!!
  • Speak to a holistic nutritionist or naturopathic doctor to help learn what foods support digestion and to determine if you have any underlying food sensitivities or allergies, which are often the issues at play.
  • Avoid common irritants and toxins such as coffee, food additives, processed foods and GMO.
  • Partake in stress relieving activities like yoga, running, sitting in nature, mindfulness practices (A detailed post on this is in the works!).

The important take home message here, is that we can no longer compartmentalize and disconnect the body from the mind (or the spirit for that matter – but that’s a later topic ;)…). If we hope to begin to adopt lasting lifestyle changes and improve our state of physical and emotional wellbeing, we must first understand, the full picture and the underlying imbalances at play that may require addressing. Remember knowledge is power. The more you become in tune with your body, your mind and their interplay, the greater your potential to reaching your balance, your vitality and all that you dream to aspire or acquire in this journey of life. Never stop learning!


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