Skin

Skin - Did you know it's our largest organ?

Skin is amazing, included in skin are its derivatives; such as the nails, hair, sweat glands and oil glands. Together these organs make up the integumentary system - the skin, and yes, it's our largest organ! The skin covers the entirety of our bodies, it is where our physical space ends, and the rest of the world begins. It is our barrier against the world. Although it may appear to be inactive, a lot more is going on than the naked eye can perceive. The skin has many functions, it goes well beyond just covering our bodies, and protecting us from the harsh environment.

So what does the skin really do for us?

· One of its main roles is that it protects us from horrible little 'infectious organisms' such as bacteria and viruses that would normally cause disease. It holds in water and specific chemicals that our bodies need for survival. However the skin itself is not completely impermeable, it does allow the passage of certain substances, such as sweat, salt and some oils. It can basically screen out what can penetrate it and what cannot, which is fortunate for us. And whist showering, it doesn't allow the water to pour into us (or out of us). Water especially is impermeable to the skin. If it wasn't we'd be in big trouble, as most of us would probably explode or shrivel up.

· The skin's pigment melanin plays an extremely important role in protecting us from the sun, although these days, with the sun becoming so strong, we need a little more help from that useful stuff called sunscreen. Melanin also gives us some of our physical individuality, some of us have naturally dark skin, and others have light. These days if you are more fortunate to have dark skin, it will offer a little more protection from the sun's rays. However, this does not mean you are resistant from sunburn and potential skin cancers.

· The skin plays an important role in regulating body temperature. If you are hot, the blood vessels in your skin will get larger (dilate), so that more blood is on the surface of your body, so that it can cool more easily. That is why you often find your face red on hot days. Sweat also helps to reduce the temperature of the body. As the moisture of sweat evaporates from the body, so does heat. When it is cold these blood vessels will get smaller (constrict), this is so that the blood is pushed internally. The reactions from skin against the hot and cold are vital in the regulating of heat, as its functions protect the temperature of your vital organs, so that they remain at a constant temperature.

· The skin also plays an important role in using the suns ultra violent rays to stimulate the skin to make vitamin D; this vitamin has many important functions in the body.

· The skin contains a vast network of nerves. These are vital to human life. As they are able to give us the sensations of touch, temperature, pressure, itching and pain. Without some of these senses, it would be quite easy to kill yourself, for example; burning yourself. And as for the sensation of pain, well there are many horrible ways you could hurt yourself if you weren't aware that you were in pain.

Some interesting facts about skin

- It has a surface area of about 1.5-2 square metres. Of course this depends on your height and weight.
- It weighs approximately 4kg (9 pounds). Again this depends on height and weight.
- It accounts for about 7% of total body weight in adults.

Your skin is extremely important as you can see, so look after it. Stay out of the sun, drink plenty of fluids (skin likes to be well hydrated) and eat a well balanced diet, so you have an adequate vitamin intake for tissue repair.

- Louise Ganey