What causes skin damage?

Skin damage is caused by ultraviolet, or UV, rays. These are invisible forms of radiation that come from the sun, and while there are three types of UV rays, only two — UVA and UVB — reach the Earth’s surface and cause damage to the skin.

  • UVA rays are long-wave rays which penetrate deeper into the second layer of skin called the dermis, though they may affect the top layers of our skin as well.

These rays are responsible for any tan that fades quickly and are the primary cause for premature signs of aging. UVA rays maintain their strength year-round.

  • UVB rays are short-wave rays which are the primary cause of sunburn and long-lasting tans. They affect the epidermis, our top layer of skin that includes skin cells, basal cells and melanocyte cells. These rays are stronger during the summer months.

Both UVA and UVB rays contribute to skin cancer, including melanoma. According to the American Academy of Dermatology, melanoma has been coined “the most lethal form of skin cancer” because it can rapidly spread to the lymph system and internal organs. It is caused from too much sun exposure.

In order to protect your skin from the sun, apply water-resistant sunscreen with a Sun Protection Factor, or SPF, of at least 15 that provides protection from both UVA and UVB rays. When out in the sun, seek shade as much as possible, especially during the hours of 10 a.m. and 4 p.m. Wear protective clothing, such as a wide-brimmed hat and long-sleeved shirts, whenever possible. Also, avoid tanning beds because according to the AAD, most use UVA bulbs.

For more information contact Courtney Britton, librarian at Cancer Services of Greater Baton Rouge at (225) 927-2273, cbritton@cancerservices.org , or visit the Education Center at 550 Lobdell Ave., Baton Rouge.


Skin Cancer Prevention – American Academy of Dermatology


Ultraviolet Radiation – World Health Organization


UVA and UVB – Skin Cancer Foundation


This column is presented as a service by Cancer Services of Greater Baton Rouge, a United Way affiliate.