UVA and UVB – Three little letters that hold a lot of impact on our health. Both UVA and UVB refer to the sun’s ultraviolet A (long-wave) and ultraviolet B (shortwave) rays. An increasing number of tanning booths, sunscreens, lotions, makeup companies and more throw around the acronyms enough to make alphabet soup.
The understanding of both UVA and UVB is vital to your skin health and helpful to understand when choosing the correct protective sunscreen, which many convincing companies advocate that they do effectively.
The science of skin is truly amazing, but here are the basics of what you need to know in order to be a responsible, keep healthy and stay young!
UV radiation is part of the electromagnetic (light) spectrum that reaches the earth from the sun. It has wavelengths shorter than visible light, making it invisible to the naked eye. Both UVA and UVB, however, penetrate the atmosphere and play an important role in conditions such as premature skin aging, eye damage (including cataracts), and skin cancers. They also suppress the immune system, reducing your ability to fight off these and other maladies.
By damaging the skin’s cellular DNA, excessive UV radiation produces genetic mutations that can lead to skin cancer. Both the U.S. Department of Health and Human Services and the World Health Organization have identified UV as a proven human carcinogen.
• UVA rays account for up to 95 percent of the UV radiation reaching the Earth’s surface.
• UVA rays are 30 to 50 times more prevalent. They are present with relatively equal intensity during all daylight hours throughout the year, and can penetrate clouds and glass.
• UVA penetrates the skin more deeply than UVB
• UVA plays a major part in skin aging and wrinkling
• UVA is the dominant tanning ray
What does this mean when it comes to choosing from a wide variety of sunscreens?
Since the advent of modern sunscreens, a sunscreen’s efficacy has been measured by its sun protection factor, or SPF. SPF indicates how long it will take for UVB rays to redden skin when using a sunscreen.
Since both UVA and UVB are harmful, you need protection from both kinds of rays. To make sure you’re getting effective UVA as well as UVB coverage, look for a sunscreen with an SPF of 15 or higher, plus some combination of the following UVA-screening ingredients:
• stabilized a avobenzone,
• ecamsule (a.k.a. MexorylTM)
• titanium dioxide
• zinc oxide.
Quick Hits on UVA and UVB Protection:
• Seek the shade, especially between 10 AM and 4 PM.
• Do not burn.
• Avoid tanning and UV tanning booths.
• Cover up with clothing, including a broad-brimmed hat and UV-blocking sunglasses.
• Usa a broad spectrum (UVA/UVB) sunscreen with an SPF of 15 or higher every day. For extended outdoor activity, use a water-resistant, broad spectrum (UVA/UVB) sunscreen with an SPF of 30 or higher.
• Apply 1 ounce (2 tablespoons) of sunscreen to your entire body 30 minutes before going outside. Reapply every two hours, or immediately after swimming or excessive sweating.
• Examine your skin head-to-toe every month.
• See your physician every year for a professional skin exam.
* Much of the factual information and images in this blog can be found at SkinCancer.org