Know Your Body: The Skin

We’re all enclosed by a delicate epidermis that carries our innards like a waterproof sack. In medical circles it’s known as the “cutaneous membrane,” but we call it “skin.”


Man Bag
It’s actually classified as an organ, and it’s our biggest one. On average it contains more than 11 miles of blood vessels (providing oxygen and blood to the skin cells), weighs nine pounds (15 percent of the total body weight), spans 21 square feet and would probably fold neatly into a trendy backpack.

Bespoke Enclosures
Every inch of it is custom-designed—foot skin is the thickest skin at 1.4 millimetres, with the eyelids the thinnest at 0.02 millimetres. 

Bac in Business
It doesn’t matter who you are—covergirl, sewage worker, royalty—every inch of your skin plays host to at least 50 million bacteria, rising to 500 million on extra-oily surfaces, like your face. These are wonderfully diverse communities (more than 1,000 species), and they help immune cells fight disease-causing microbes.

Magic Touch
There are at least five types of receptors in the skin that respond to pain and touch. The most sensitive of these are the tongue, lips, palms, fingertips, clitoris, penis and nipples: Areas that can respond to a pressure of just 20 milligrams, or the weight of a common housefly.

I Feel Brand New
Depending on your size, you can have roughly 1.6 trillion skin cells, each one programmed to systematically destroy itself as it reaches the skin’s surface. You will also shed enough skin cells in two minutes to cover a football pitch—nine pounds’ worth over a whole year. Oh, and get this, every 28 days our entire skin will be renewed. Yep, the whole lot will be regenerated. That’s superhero stuff.