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Sunscreen and Sunblock

Sunscreen and Sunblock Facts

  1. The sun produces ultraviolet radiation that can result in undesirable changes in human skin.
  2. A limited amount of sun exposure can produce beneficial effects to the body as a whole.
  3. Skin darkening (tanning) in response to exposure to sunlight is a sign of potential skin damage.
  4. Chemicals or clothing placed on the surface of the skin that either absorb or block ultraviolet solar radiation can act as a sunscreen or sunblock.
  5. The major long-term undesirable effects of sunlight on skin are the development of skin cancer and photo-aging.
  6. Sunburn is an unpleasant and painful immediate short-term effect of excess exposure to sunlight.
  7. There are naturally occurring substances in the skin, melanin for example, that offer a degree of protection from ultraviolet radiation.

History of Sunscreen

Originally sunscreens were looked upon as preventatives for sunburn. Over the last 50 years, our understanding of the negative effects of ultraviolet light has evolved. It was believed that the sun was beneficial for skin, producing a darker coloration and an enhanced feeling of vitality. Now it is known that extended exposure to sunlight has very limited beneficial effects and will cause wrinkling and produce mutations that predispose to almost all cases of skin cancer.

How Does Sunscreen Work?

Sunscreens work by absorbing or reflecting ultraviolet light so that it does not reach the living cells of the skin or the deeper, collagen-rich dermis.

Medically Reviewed by a Doctor on 5/27/2014
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Patient Comments & Reviews

The eMedicineHealth doctors ask about Sunscreen and Sunblock:

Sunscreen and Sunblock - Preferred Brand

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Sunscreen and Sunblock - Ingredients

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Sunscreen and Sunblock - Sun Protection for Babies

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