The Human Body

Last modified: August 6, 2020
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“Advances in science and technology have shown that, really, a physical body is a universe in itself. Each of us is made up of roughly a hundred trillion cells. In each of those cells is roughly that same number again of atoms. That is a lot of separate components. Our brains alone have a hundred billion brain cells, give or take a few billion.”

Reasons to Stay Alive by Matt Haig

‘I’ think it’s worth reminding ourselves of the actual scale of what Matt mentions in the quote above by revisiting the following tweet again…

So, what you probably think of you is actually 100,000,000,000,000 individual cells working together in an anti-rivalrous way to make you ๐Ÿ™‚

This HUGE number is actually still just a best guess estimate from what ‘I’ can find out myself. However it has also been suggested that that up to half of all cells in OUR Human body are actually not even ours as they are actually from bacteria!

So not only is it a miracle that you are here at this moment reading this, (as per earlier in this documentation) but you are most probably not made of more than 50% human cells ๐Ÿคฏ

The craziness doesn’t stop there though, as in addition to the foreign bacteria making you, WE also host single cell organisms called archaea, as well as viruses, fungi and other microbes all within what is known as the human microbiota. Even what WE think of as OUR human cells carry DNA from mitochondria which are the descendants of bacteria.

These different clusters of genetic material in different parts of your human body – for example your skin and your gut have very different microbe communities known as microbiota. Taking the gut microbiome as an example, there has been a great deal of biological research investigating how your gut and it’s bacteria can cause diseases and conditions as varied as diabetes and obesity as well as autism and anxiety!

For more microbiome information ‘I’ suggest looking at defining the human microbiome which is a review paper from 2012 that highlights recent research.

WE can also quickly see via the wonderful internet that several studies show that up to 60% of what you know as the adult human body is also actually water – see here.

The somewhat shocking statistics of what you actually are in terms of your physical Human Body don’t stop there though…

Every cell in your body also has it’s own lifespan and therefore you are physically a new you in certain regards multiple times in your life whether you like it or not – growth and rebirth is part of Human nature ๐Ÿ™‚

However your whole body and cells don’t regenerate fully every 7 years as some basic blog posts and memes would suggest. For instance, the cells that line your stomach wall are replaced every few days due to their constant contact with your digestive acid. However your skin cells have a lengthier lifespan and are renewed every two to three weeks on average.

Your red blood cells average around 4 months but your white blood cells that fight infections can die in as little as a few days or last just over a week. One of the longest living types of cells are OUR fat cells alongside your bones which both average around 10 years however unfortunately you can’t regenerate your main brain cells, tooth enamel or the lenses of your eyes. For more cell age related data take a look here.

Human Eye Sight

In terms of cells in your eyes, on average, WE Humans can see around 1 million different types of the sensation WE call colour. This sensation occurs when light of different wavelengths hit each of three separate cone cells at the back of OUR eyes which then sends messages to our brain and combines these signals into what WE see as colour. This standard model of colour vision is known as Trichromacy.

However research from 2012 showed some humans (all of whom were women) are actually capable of and actually see 9 million more colours than the rest of us! These people are known as tetrachromats and are able to make full use of an extra cone cell they have. For more detailed research and analysis on this genetic quirk click here .

If most of us Humans can only see 10% of what some other Humans can see in terms of the sensation of colour then…

Does that mean most Humans don’t see reality as it ACTUALLY is or that WE can’t ever have the FULL Human experience tetrachromats have?

This concept of the Human experience and where it is produced is covered more in the next section the Human Mind but for now lets also talk about where these sensations are generated in what WE call the Human Brain…

Human Brain

OUR Human brain can process around 11 million pieces of unconscious information per second. However OUR brain’s conscious processing ability, this is the bit WE think WE are in control of each day, is thought to be only able able to handle around 40 pieces per second.

This means your own brain is capable AND constantly handling in the background ALL those physical and mental actions you take for granted such as breathing, blinking and a whole lot more of the ‘boring’ day to day stuff without you even being aware of it! A lot of this happens via the Autonomic Nervous System as part of the wider Nervous system and in coordination with the endocrine system.

For instance let’s take blinking, something needs to first decide to send a signal to all the cells and muscles in your eye lids at set times to run the command known as blinking in order to keep your eye balls moist. Does your unconscious brain decide this should be performed every 5 seconds as standard then generate the electrical signals to do this based on previous experiences? Is this decision actually normally based on information within your DNA that a relative passed to you or maybe the default interval is based on how much moisture is in the air at the moment or a combination of all these?

‘I’ am already way out of MY depth on such matters but ‘I’ think it’s safe to say that without such unconscious processing WE as a species wouldn’t even be able to get through a fraction of what we call ‘life’ each day. Our lives would certainly have never developed to the point where WE are having this discussion now either!

The indisputable fact is that OUR own bodies and brain control and hide OUR true reality in terms of how WE are even able to function as Humans all the time never mind higher functions like sensation and OUR consciousness etc

The above realisations are so profound that countless philosophers, scientists and ordinary people have dedicated their entire lives trying to get to the bottom of such matters. In fact your Human brain and the whole thing WE collectively call consciousness is such a HUGE topic that this is explored within it’s own dedicated part of this documentation later but for now let’s move onto the term for how your brain changes based on your life experiences…


Neuroplasticity is in the most simplest terms, is the ability of your brain to change continuously throughout your life. you can obviously read more on this by following the previous link ‘I’ have provided for you but ‘I’ only want to mention this in passing at this point in order for you to know no matter how much you think you can’t learn new skills and ways of thinking, neuroscience says you can!

‘I’ am not saying this process isn’t hard though as there is something called the Backfire effect, which again you can read more about via this web page and great podcast as well as this long web page and comic, but can be summarised as…

In the face of contradictory evidence, OUR established beliefs do not change but actually get STRONGER.

Time Out

If you have at least scrolled through the long web page comic above about the backfire effect are there some examples that spring to mind when you have suffered from this?

‘I’ am going to discuss many ways that ‘I’ can hopefully help you rewire your brain later in this documentation and hopefully mitigate effects such as the backfire effect but next up let’s look into what we think the Human brain contains, the Human Mind…

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