Ultraviolet (UV) rays are a part of
sunlight that is an invisible form of radiation. UV rays can penetrate and
change the structure of skin cells and can cause skin cancer and premature skin aging. Exposure to
UV rays from the sun or tanning beds is the most preventable risk factor for
melanoma. UVA rays are the most abundant source of solar radiation at the
earth's surface and penetrate beyond the top layer of skin. Scientists believe
that UVA rays can increase a person's risk for developing skin cancer. UVB rays
are less abundant at the earth's surface and penetrate less deeply into the
skin but can also be damaging and are primarily responsible for causing
sunburn. It is important to wear a broad spectrum sunscreen that protects
against both UVA and UVB radiation. The current SPF scoring system primarily
refers to degree of protection against UVB radiation, and scientists at the FDA
are working to develop and implement a system to measure UVA protection.
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