There is a lot of chatter on the internet about our Gut Brain connection. It would be helpful for us to understand exactly what that really is.
If you asked a conventionally-trained Gastro-enterologist about guts and brains, he or she would say that those are two separate systems. The Gastro-intestinal tract or the digestive system, is a system quite apart from and distinctly separate from the neurological system that makes up our nerves, spinal column and brain.
When does the gut brain connection start?
So to find out what this gut/brain connection may be, we need to go back to our early days in the womb and understand what stages we go through in our embryonic development.
Initially after conception, we are a blackberry-like blob of rapidly-dividing and multiplying cells which cluster together. Soon, they start to differentiate and take on different qualities; a forerunner of the different types of cells they will eventually become in the fully formed human baby.
The first two structures that form are two tubes (this is a vast oversimplification, of course!); these first two tubes will go on to form the digestive tube and the neurological tube. Sitting in the middle is the heart (which starts to beat extremely early on), and the circulation is starting to form around the two tube-like structures to serve them with fresh oxygenated blood and nutrients. The digestive tube starts to elongate, twist and bud out the accessory organs like the liver, pancreas and gallbladder and the neurological tube starts to branch into finer and finer branching structures forming the neural network that goes all over each and every part of our internal organs. This early development makes it easy to imagine that the early structures are energetically and biologically linked because they came from the same stuff and developed in parallel.
The forebrain, in all its complexity, is the last part of the structure to develop and is late to the party. After all, basic survival needs respiration, nourishment and elimination, it doesn’t need thinking to survive, so that comes last!
These early structures show that the two systems are closely related and develop together, linked as closely as the blood supply that feeds them both.
Looking at the function rather than just the anatomy, we need to consider what our early developing biology demanded of the two systems.
How does the fight or flight reaction affect your gut?
Imagine you are Stone-age man, currently being hotly chased by a hungry sabre-toothed tiger. Your body is pumping blood and oxygen to your legs, arms and lungs to keep you running and breathing as fast as possible for survival. This is not the time to need a bowel movement (your hungry tiger won’t accommodate your need for a potty-stop), so your digestive system is shut down and denied blood and nerve energy for that emergency moment.
Once you are safely back in the cave, avoiding capture and being Felix’s dinner, you can relax. Your heart rate slows, your blood supply is pumped back into the internal organs and your muscles can relax. Now is the time for your digestion to ask for attention and energy. There are actually two nervous systems competing for attention in the body – the Fight or Flight stress response is the Sympathetic nervous system (think Sympathy for your Stress) and the relaxation one, which allows for repair, renewal, regeneration, reproduction and digestion, is the Parasympathetic nervous system (think Peace = Parasympathetic). They take it in turns, according to the external stimuli.
So, the brain tells the gut when it is allowed to get to work and when it must take a back seat.
How does our gut inform our brain?
Likewise, we use our gut to inform our brains; we use terms like “gut reaction”, “sick to my stomach”, “gut instinct” etc, to help us make decisions.
Those of us who work in natural health and holistic therapies will readily agree that upset digestion, IBS, dysbiosis or any other gut-related condition will easily trigger or cause mental states like depression, irritability and even more subtle things like brain-fog, difficulty concentrating and even some autistic-like symptoms and behaviour.
The link is two-way. The Gut-Brain connection is a circular one which has no beginning and no end.
How does a high stress lifestyle affect your gut?
One word of warning, the demonstration that stress situations stop the digestion is a clear caution that staying in a state of stress – and our modern version of the Sabre-toothed tiger is probably the Taxman and impossible to outrun – we may stay constantly in a state which doesn’t give our digestion its full energy and resources. We are metaphorically running away, or at least ready to run away, from our version of Felix all the time.
This makes it hugely important to make mealtimes calm; rest after eating and find a relaxation or meditation practice that gets you out of your Sympathetic stress response and into a more peaceful, Parasympathetic state.
Your gut and brain both depend on it.