Composite layer of human skin like a layer cake layer. Outermost layer of skin called the epidermis, there is a layer in hides and fat layer. In the epidermis there are cells that are useful for skin turnover and eumelanin pigment-forming melanocyte cells in which there melanosom melanisasi scene of the pigment eumelanin formation. As described above, the function of eumelanin is as protective skin from the sun, in addition to skin coloring. The person who is black, his melanocyte cell more than white people, so it is more resistant to sunlight stings. In contrast, white-skinned people, exposure / exposure to sunlight easily penetrates the cuticle layer, flammable, and skin cancer.
The strength of sunlight depends on the type of ultra violet (UV) contained. Types of UV light comprises ultraviolet light A (UVA), ultraviolet B (UVB) and visible light. UVB rays with shorter wavelengths, is filtered by the ozone layer to reach the earth's atmosphere with a fairly high level and lead exposure in the epidermis with symptoms of burning (sunburn) or brown (Sutan). Meanwhile, UVA rays have lower energy, but is able to penetrate the layer of fat on the skin. UVA is responsible for damage to collagen and elastin network, which is a substance that makes skin strong and supple. What should be done to ward off the sun? First, experts recommend always using a sunscreen when exposed to sunlight. Sunscreen there are many different types. There is a form of cream, liquid, gel, or foam. It is best sunscreen containing SPF and in accordance with our skin type. Substance SPF is the ability of a sunscreen to reduce the amount of UV rays that reach the skin. If the there is an SPF 15 sunscreen, means the skin will burn for 15 x 20 minutes = 300 minutes. Twenty minutes was the limit of tolerance of skin and UV shock. Outstanding Sunscreen and SPF 2 to SPF 34. In choosing a sunscreen should also be noted skin types. What is the condition of oily skin and acne? If yes, choose a sunscreen that is free of oil or non-komedogenik. Chemical sunscreens contain active ingredients class of PABA (para amino benzoin), non-PABA, and combinations. PABA Group impede or block the UVA rays (which makes pigmentation abnormalities), whereas the blocking of UVB (rays that cause sunburn) is weak. Sunscreens contain a combination of more and one active ingredient and protects skin, and UVA and UVB. By knowing a variety of sunscreen, it's nothing more to be feared consequences that occur due to sun exposure.
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Caring for Skin & Face By dr. Maria Dwikarya, DSKK