Added: 01/27/2006 |
How the sun protection factors workIt is a well-known fact that sun-protection creams and other sun-protection cosmetic are intended to protect the skin from the negative influence of ultra-violet beams, however, hardly anyone can explain why it is necessary to protect yourself from the sun and how the sunscreen work on the skin.
Ultra-violet beams are divided into three groups, depending on the length of waves. Group C is characterized by the wavelength of 200-290 nanometers. This kind of radiation hardly reaches the surface of the ground. Group B includes waves ranging from 290 to 320 nanometers. This radiation is capable to penetrate through external layers of epidermis and damage skin cells. Group A is characterized by the length of 330-400 nanometers. These waves penetrate into deep skin layers and damage fiber molecules, forming free radicals.
Sun-protection creams are based on the action of sun protection factors. The sun protection factors reviews differentiate three basic sun protection factors: physical UV filters, chemical UV filters, and antioxidants.
Talking about physical UV filters, we should mention that such filters include micro particles of titan dioxide and zinc oxide. The smooth surface of micro particles reflects ultra-violet radiation. However, sun-protection creams have these components in relatively small quantities.
Chemical filters are most effective sun protection factors. Chemical filters are created with substances containing benzene, metoxycinnamate oxide, and other UV filters, and are designed to transform ultra-violet radiation into thermal energy, thus precluding solar radiation from getting into the skin. Some years ago, sun-protection creams also included sulfanilic acid. Today, this substance has been forbidden for use for fear that it may cause allergic reaction. Certain experiments have proven that fact.
Antioxidants constitute the third group of sun protection factors. They restore the damaged epidermis cells and neutralize the negative impact of free radicals, which may accelerate the ageing processes of skin cells. Among natural antioxidants are vitamin E and vitamin C. They effectively contribute to normal functioning of cells and increase immunity of epidermis cells. The majority of sun-protection creams also include vitamin A. This vitamin is not an antioxidant; however, it restores skin cells after the sun-burn. Besides, it strengthens skin cells and normalizes the epidermis metabolic processes.
Cosmeticians recommend using sun-protection creams with protection depending factors. Sunscreens are to be applied 10-15 minutes prior to exposing oneself to the sun. Before using the sunscreen, one should test whether the skin is allergic to sun-protecting substances contained in creams. It can be done by applying a little amount of cream on the elbow. If in ten minutes the skin reddens, it means that you are allergic and the cream should not be used. If the skin retains its natural color, the sunscreen may be applied.
Article comments:
No comments for this article yet. Post your comment now!
