Welcome to a frank, funny and poetic dive each month into a different part of the bundle of flesh that is your body.
Hey there. We already know each other – right? We’ve been besties from birth, even though we sometimes fight. I might even have heard you say you hate me (yeah, that’s hurtful). But I forgive you – you’re human. I’ve always been there for you. And I am a little weird.
Even though we’ve spent so much time together, sometimes I wonder if you really know me. I know you’ve been wondering too. So I thought maybe it’s time for you to really get to know me.
You know how annoying it is when people take just one look and assume they know everything about you? When, actually, you go far deeper than what they see.
Yes, I may be beautiful, but I’m far from superficial. I’m complex and layered, and like yourself, I have many hidden talents.
Of course, it’s only natural that I’m the first part of your body to introduce myself. I’m your largest organ, after all – I make up 15 percent of your bodyweight, contain 17 kilometres of blood vessels and millions of sweat glands. And hair. Did I tell you about my amazing hair? I was born with 5 million hair follicles, a number that does not increase or decrease throughout your life. (Hyperbole is one of my special skills).
I’m also a complex interweaving of three distinct layers. The part you see when you look in the mirror is the epidermis. It contains tiny nerve endings, a protective layer of keratin (a type of protein) and melanin, the pigment that makes your skin light or dark. There are also immune cells called Langerhan’s cells (named after a man, like most of the structures in the body), and mysterious sensory cells called Merkel cells (sorry; also named after a man, also German).
My next layer down is the dermis, a fertile, nurturing bed which contains blood vessels, hair follicles, more nerves, sweat glands, sebaceous glands that secrete oil, and collagen and elastin, which make me smooth and stretchy. (It’s weird that people think they can boost these by applying creams; it’s not that simple, but I guess that’s the power of wishful thinking).
My final layer is the hypodermis, a cushion of fat and collagen that cushions and insulates, as well as storing energy. Yes, sometimes this is the part you hate, pinching and grimacing in front of the mirror, but believe me, my design has been well-thought out. I’m the product of millions of years of evolution.
I adapted to challenges by developing unique talents. When you started using tools and thinking things through, you had to cool your increasingly large brain. I’m all for large brains, so I solved your issue by reducing the thickness of my hair, which helped blood vessels release their heat easily. I kept the top of your head covered, to protect it from burning in the sun (I’d still recommend a hat and Slip-Slop-Slap, though!)
Speaking of evolution, it’s a common misconception that my colour evolved as a response to sun exposure. It did, but it wasn’t to protect against UV radiation. In fact, it was to enhance the production of two key vitamins. Let’s start with the first. Vitamin B9, also known as folic acid, aids in the formation of the brain, spine and skull as well as your red blood cells: in other words, you’re pretty stuffed without it. Folic acid is destroyed by sunlight, so initially, when I evolved to have less dense hairs, I also darkened to preserve folic acid so you could have healthy babies.
But this became an issue when humans migrated from Africa to countries further away from the equator. Here, less sunlight meant that vitamin D didn’t achieve a vital chemical step to be made, putting you at risk of having babies with rickety bones and weak immune systems. So I had to lighten my colour again. And ever since, it’s been a juggle between two needy dependents. Sound familiar?
This might be obvious, but I never intended the evolution of my colour to become a political statement or a means to divide or discriminate. Truly, your survival was my only goal. Everything else is . . . well, it’s not really about me, is it?
In a way though, I do make borders. I make your border. I am what defines you: what people see when they first look at you. I hold in your bits, wobbly or not. (No judgement from me). I separate the inside of you from the outside of you.
That also makes me your border in terms of defence. No, I’m not just a pretty face. I’m bristling with weaponry: immune cells (not just the ones named after Germans), arrayed in special crypts, ready to ID and execute any microbe with malign intent. But equally, I welcome the friendly microbes. More than welcome: I’m their home, sponsor and beneficiary. I call them “friends with benefits” but scientists prefer to call them the skin microbiome. As with any healthy country, having diversity in your population is desirable. And sexy.
A question you could help me with: how come the outside world ascribes virtues to you because of me? I mean, how can you help how I look? We all age, right? I am not to blame for the beauty industry – that’s out of my control. In fact, I’m mostly out of their control, despite what they claim. Burn.
I can look after myself, mostly. Magically, I renew monthly, shedding the cells on my outermost layer. My epidermal cells are sacrificial warrior maidens, defending you (and your looks) with their death. They are born from the division of plump motherly basal cells, who never see the light themselves, but send their daughters on a one-way journey to the surface (yes, I enjoy a bit of mythology).
Over a month these virgin cells rise, drying out like raisins, losing their vitality and eventually even their nuclei. Their lifeless, flattened, keratin-filled bodies eventually reach the outside world and fall like snowflakes – the strong type. There’s a certain dark comedy in knowing that when people look at me in judgement, what they’re judging is already dead.
But I’m not dead all the way through. Far from it. I’m the living, throbbing centre of your feelings: my last great talent. Through me, you perceive everything. I let you know pleasure – the soft flicker of fingers across my surface, making those tiny nerve endings writhe in ecstasy. I tell you whether it’s hot, cold, or just-Goldilocks-right. I let you know pain, too, through those millions of nerves. The pain is meant to protect, but I’ve been known to get it wrong, and I’m sorry. I respond to everything that affects you – physical and also emotional. As I said, I’m complex.
So that’s me for now. There’s so much more to tell you – but some of the other parts of your body are keen to speak. Nice to meet you – I am your skin.