Most of us think of our skin as a bag that holds our bodies together but it is in reality a lot more than that. It is a very complicated part of our body that is made up of three layers-the epidermis, dermis and subcutaneous layers. Among other things, our skin protects us from sun, water, infections, injury, pain, heat and cold while also storing energy, healing itself, acting as a shock absorber and producing vitamin D! But those are not as surprising as the following five facts:
1) It is the largest and heaviest organ in our bodies, weighing about 20 pounds in the average adult. The thickness of the epidermis, which is the skin's outer layer, ranges from half a millimeter in our eyelids to 4 millimeters on the soles of our feet. The next layer is the dermis and is several times thicker, mainly in the upper back, followed by the fatty subcutaneous layer which contains nerves, arteries, veins and lymph vessels with every square inch of skin containing about twenty feet of blood vessels. Stretched out, the skin of the average adult measures about as much as a twin size bed sheet.
2) We have between 3 million to 5 million hairs on our skin.
3) Our nails, which are part of our skin, grow faster in the summer with fingernails growing faster than toenails. On average, our nails grow between 0.5 millimeters to 1.5 millimeters every day.
4) We grow a completely new epidermis every month and about 1,000 skins in every lifetime. Every time you walk into a room, you are trailing a plume of microscopic skin particles that are flaking off your body to the tune of about 10,000 skin cells per minute or about 1.5 pounds of cells per year. That literally means that you are not the same person when you walk out the door as the one that walked in! In fact, most of the "dust" in a room is human skin dust and we are all breathing pieces of each other in all the time!
5) Our hairs have muscles that cause them to stand on end when we are cold or afraid. We call this effect "goosebumps" and it is most likely a left-over from very early human history, when we were more like the other living beings on planet earth. Notice your cat's hair standing erect when she is scared? Well, she does this to look bigger and scarier to other animals and we probably did the same back when we were as hairy as her!
