Your Skin, the basics

Before we delve into the fabulous world of skin type lets take a short detour and learn some basic (I promise you I won't ramble on!) physiology. Just knowing the physical make up of your skin will make it so much easier for you to cut through all the nonsense of those so called "miracle" products and enable you to make the best possible choice for your skin. Your skin isn't just a gorgeous layer of loveliness; it does some very important work. It provides protection from the elements, maintains your body temperature, eliminates toxins, protects you from all sorts of bacterial nasties and best of all is home to all those gorgeous nerve endings which give you your glorious sense of touch!

Epidermis
The epidermis is constantly being renewed. It takes around 28 days for the skin cells to travel from the base of the epidermis to the top, unfortunately this process slows as we age. This is why many skincare companies produce quite harsh skin treatments to irritate the skin and slough off dead cells in the hope of speeding up the process of epidermal regeneration. Unfortunately these harsh products are extremely effective causing the skin to become irritated and inflamed. Even more worrying is the fact they thin the skin making it even more susceptible to sun damage & broken capillaries! Your epidermis has six layers (don't worry, I won't bore you, I'll just stick to the need to know!). The uppermost layer (the bit you can feel) is called the stratum corneum. It's tightly packed with scaly cells called keratinocytes. These cells are little elevators that move upward from the bottom of the epidermis to the top, but on their journey they stop at every floor to fill up with keratin. Keratin is a tough little protein that provides the skin with its waterproof barrier. The barrier that those cells create forms a protective layer that protects against harm from water loss, pollutants and unfriendly bacteria. At the base of the epidermis you will find melanocytes. These fab little cells are responsible for producing melanin, which protects your skin and the underlying tissue from sunlight. Melanin produces the pigment that causes your skin to tan. Melanocytes produce and move melanin in cells called melanosomes; these little cells are then taken up by the keratinocytes on their journey to the top of the epidermis.

Another Good Reason To Use SPF
The epidermis also contains Langerhan cells, which provide protection for the immune system against invading micro organisms, viruses and bacteria. When skin becomes damaged by UV radiation it also damages the Langerhan cells, causing few to survive in the skin and carry on providing protection for your immune system.

Dermis
Located directly under the epidermis, the dermis acts as a support. This is the skins most active layer, its where the most vital functions take place. The dermis contains (amongst other things!) blood vessels, nerve fibres, lymph glands and of course collagen and elastin. Collagen and elastin are that wonderful duo of fibres that give your skin its flexibility and strength. Think of them as a firm mattress providing your skin with real tone. Collagen and elastin's mortal enemy is the sun. UV rays are kryptonite to this fabulous duo, causing them to become damaged which in turn causes skin to become wrinkly and saggy (the not so fabulous duo!).
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