Back in 1989 I went to a lecture on something called the Vagus nerve. It excited me (no pun intended for the scientists among you) and without a doubt held a key to health. From my understanding back at that time the Vagus was the master nerve. It left the brain and descended down the neck, all the way down the body branching off on route to every organ you could possibly think of. Its big thing was calming the body down, relaxing it and if you ever feel tired after a big meal and want to sleep, the Vagus nerve is partly behind it. In other words, it was the nerve that conveyed information from the automatic system of the body (autonomic nervous system), that we had little conscious control of. Now I could talk all day about autonomics and it is at the heart of healing and Osteopathy but for today I would like to focus on the other flow of the Vagus. The flow not from the brain down to the organs but from the organs to the brain. More specifically, from the stomach to the brain.
A slight detour and you will see why in a minute.
Research has been pouring out in the last few years about something called the microbiome, and if you haven’t heard of it, chances are you have not been chatting with me for a few years. I am slightly obsessed with it. We are after all made mostly from bacteria, fungus and ancient virus. The fabulous book 10% human, is a read I often recommend and can really show the balance we have with surrounding life forms. The fact we have only 20-25 thousand genes in our bodies (thank you the human genome project) is slightly worrying as a carrot has more than we do, 33 thousand. I would hope most of you agree that we are slightly more complicated than a carrot. However, as most of us is not human, we get bacteria etc to do the work for us and when you combine the number of genes in bacteria and humans you are now talking tens of millions. In short, don’t think you are all human, most of you isn’t, yet our ability to work with these bacteria or their ability to work with us, is why we are so special. At least that is what my mother tells me I am.
So why is it we tend to ignore the majority shareholders of what we are (bacteria) and what does this majority shareholder do? For a start it digests our food, it regulates our immune system, it literally makes vitamins and stops harmful infections. Trillion of bacteria, etc reside on our skin, in our every organ and even conjugate in huge numbers in hairy sweaty places wafting their smells and odours to attract mates and ward off unwanted attention. Our gut is jam-packed full of them and they very much are in control.
But hold on, before I enter the huge chasms of what does what and where– we are talking Vagus and this is the link I want to focus on. You see, what we eat and how it is digested is what feeds the microbiome. A delicate balance is responsible for breaking down sugars, proteins, fats etc. Certain foods allow the reproduction of some bacteria more than others. Indeed certain foods may kill off some bacteria. Of course, what bacteria is in there to start with is key and that means we have to think mother and birth (more of that later)
The internal and established bacteria now leads to constant war. Just like all life, bacteria fight for an advantage and it is a dirty grubby rumble to say the least. Imagine armies of certain bacteria and armies of another fighting for the position of power, reproduction and land, but in their trillions. What tactics do you think they would take, maybe similar to the tactics we employ ourselves in war. Dirt and backhand perhaps? Maybe you thought fake news and manipulation was uniquely human… Think again. We know that some bacteria in animals force their owner to act in a certain way. For instance, a toxoplasma bacteria change a rats brain from instead of being afraid of its primary predator, a cat, to switch it to actively seek out a cats urine. It makes the rat want to be caught and eaten. That is because this bacteria (Toxoplasma) only can reproduce inside a cat. It actually has a plan. To be fair, it may not have a cunning plan, it just is….(philosophers delight)
So why do we ever think that bacteria and fungus can act on other animals but not effect us in the same of similar way. Lots of bacteria has now be shown to do exactly that. Toxoplasma as an example has been shown to effect men, by making them more reckless and yet makes women more trusting. Could this be yet another way it gets it host to reproduce? Some girls really do like a bad boy despite all that logic. Some research has now linked that same bacteria to schizophrenia and autism. Could it be possible that bacteria, out of control, or out of balance, changes our nature and behaviour. My answer would be yes and don’t take my word for it, science agrees.
Just as a background , toxoplasma is found in many cats. Humans can get it from a cat scratch or dealing with the litter tray. One experiment showed 22 % of Parisian pregnant women to be infected. Think about that next time you are on a romantic break in Paris!
Another such example is the behaviour of high neuroticism and low conscientiousness.(hnlc) When tested (see reference below) re a large scale personality test for the above – hnlc people had high levels of Gammaproteobacteria and Proteobacteria in the gut. Additionally, highly conscientiousness people showed increased abundance of some butyrate-producing bacteria like Lachnospiraceae and others.
This is a minefield as these bacteria are in terms of relative to body size distance millions of miles from the brain and our supposed personality.
This of course is where the Vagus nerve comes into play. It sits proudly by the stomach, soaking up bacteria and its by-product. Avoiding the famed blood-brain barrier, it railroads the chemicals straight to our brain. We think now that this is the mode of transport. Recent studies have certainly shown plaques appearing by its retrograded flow and some research has even linked these plaques to degenerative disease of the brain.
Let us think about how we populate our gut. Mostly the first few seconds of life and certainly the first three years make all the difference in the world. We know that children born in C section have a higher incidence of asthma and eczema and food allergies that natural, vaginal born children. The thought is the covering of bacteria from a mother’s womb during childbirth populates the child and immediately stimulates the immune system. The old saying, a little bit of dirt is good for you is very true.
Now , I could and will talk and explore this topic for hours, and if you are ever having treatment and want to know more, please do ask….please… For instance, don’t get me started on antibiotics in children for ear infections………………………
as a side note, we have lived with bacteria forever, if you consider that the life of the earth is about 4.6 billion years old and it took about 3 billion years to develop simple life, and another billion years to develop animals, think about that friendship / relationship. Humans in our current are a mere 250 thousand years and so we have in our every cell (almost) a powerhouse of converted bacteria called mitochondria. Trillions of bacteria and fungi are on every part of our body inside and out. We truly would not be here without it and so we, our mother, our mother’s mother have hosted these bacteria since the dawn of animals. No animal can live independently of its microbiomes.