Take a closer look at the number one cause of skin cancer: Ultraviolet light, and learn to protect yourself!
Ultraviolet light, otherwise known as UV rays, is actually a form of invisible radiation from sources such as the sun, tanning beds and to a lesser degree even overhead fluorescent lighting. UV rays can penetrate and even mutate the cellular structure of our skin cells.
Know the difference
The three types of UV rays are ultraviolet A (UVA), ultraviolet B (UVB), and ultraviolet C (UVC).
UVA
UVA rays are the longest of the three wavelengths and make up 95% of the UV radiation that reaches Earth’s surface. UVA is the most common kind of sunlight at the earth's surface, and reaches beyond the top layer of human skin all year round, in sunshine, clouds, or rain.[1] Scientists believe that UVA rays can damage connective tissue and increase a person's risk of skin cancer. 80% of UVA rays can pass through clouds and damage your skin.[2]
They are present with relatively equal intensity during all daylight hours throughout the year, and can penetrate clouds and glass.
UVA, which penetrates the skin more deeply than UVB, has long been known to play a major part in skin aging and wrinkling (photoaging), but until recently scientists believed it did not cause significant damage in areas of the epidermis (outermost skin layer) where most skin cancers occur. Studies over the past two decades, however, show that UVA damages skin cells, contributes to and may even initiate the development of skin cancers. [3]
UVA rays are predominantly responsible for squamous cell carcinomas.
Image source: Cancer Research UK.
UVA rays reach much deeper into your skin than UVB rays. The ozone layer absorbs most UVB rays; UVA rays, on the other hand, reach deeper into the skin, past the outer layer (the epidermis) and far into the dermis and hypodermis.[4]
Rays can have dramatic negative effects on your skin. Because UVA rays penetrate deep into the skin (the dermis and hypodermis), UVA ray damage is responsible for premature aging, including loss of elasticity, wrinkles, sunspots, fine lines and hyperpigmentation.[5]
Image source: Cancer Research UK
While UVB rays are only present when the sun is out, UVA rays are always present, even when it’s winter. Even if it’s cold and dreary out, you still need sun protection to guard against UVA rays.UVB rays are most intense when the sunlight is brightest—between 10am and 2pm. UVA rays’ intensity is constant throughout the day, regardless of whether or not the sun is directly hitting you.[6]Unlike UVB rays, UVA rays can penetrate glass windows, like your car windows. At least 60% of UVA rays can pass through car windows.[7] Even when you’re driving, UVA rays can still damage your unprotected skin. This is why we created our classic Sundriven gloves to help protect you.
UVB
Most UVB rays are absorbed by the ozone layer, so they are less common at the earth's surface than UVA rays. UVB rays don't reach as far into the skin as UVA rays, but they can still be damaging. The shorter length rays of UVB are primarily responsible for the reddening and burning of our skin.
UVB plays a key role in the development of skin cancer and a contributory role in tanning and photoaging. Its intensity varies by season, location, and time of day. The most significant amount of UVB hits the U.S. between 10 AM and 4 PM from April to October. 70% of a person's yearly UVB dose occurs in the summer. [8]
However, UVB rays can burn and damage your skin year-round, especially at high altitudes and on reflective surfaces such as snow or ice, which bounce back up to 80 percent of the rays so that they hit the skin twice. UVB rays do not significantly penetrate glass. [9]
Both the powerful UVA and UVB rays, that make up in part the term UV radiation, can be extremely harmful and dangerous when we are not taking proper precautions.
Many experts believe that, especially for fair-skinned people, UV radiation also frequently plays a key role in melanoma, the deadliest form of skin cancer, which kills more than 8,000 Americans each year[10] Did you know that melanoma is the most common form of cancer in adults between the ages of 25 and 29?[11]
Image source: The American Academy of Dermatology
UV radiation is considered the main cause of nonmelanoma skin cancers (NMSC), including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). These cancers strike more than a million and more than 250,000 Americans, respectively, each year.
So do yourself a favor: Wear SPF and make sure you buy yourself proper sun protective apparel. Our ageless Sundriven collection was designed just for that, and is stylish to boot.
Follow these tips from the American Academy of Dermatology when applying sunscreen:
- Choose sunscreen that has an SPF of 30 or higher, is water resistant, and provides broad-spectrum coverage, which means it protects you from UVA and UVB rays.
- Apply sunscreen generously before going outdoors. It takes approximately 15 minutes for your skin to absorb the sunscreen and protect you. If you wait until you are in the sun to apply sunscreen, your skin is unprotected and can burn.
- Use enough sunscreen. Most adults need at least one ounce of sunscreen, about the amount you can hold in your palm, to fully cover all exposed areas of your body. Rub the sunscreen thoroughly into your skin.
- Apply sunscreen to all bare skin. Remember your neck, face, ears, tops of your feet and legs. For hard-to-reach areas like your back, ask someone to help you or use a spray sunscreen. If you have thinning hair, either apply sunscreen to your scalp or wear a wide-brimmed hat. To protect your lips, apply a lip balm with a SPF of at least 15.
- Reapply sunscreen at least every two hours to remain protected, or immediately after swimming or excessively sweating.
UVC
UVC rays are in fact, very dangerous, but they are absorbed by the ozone layer and do not reach the ground. These rays have the shortest wavelength, the most energy and fortunately do not penetrate the atmosphere. UVC radiation is almost completely absorbed by the ozone layer and does not affect the skin.[12]
Authors: Mitzi Runyan & May Jabado
Sources: [1] http://www.skincancer.org/prevention/uva-and-uvb/uva-radiation-a-danger-outdoors-and-indoors
[2] http://www.aad.org/media-resources/stats-and-facts/prevention-and-care/sunscreens
[3] http://www.skincancer.org/prevention/uva-and-uvb/understanding-uva-and-uvb
[4] http://www.cdc.gov/cancer/skin/basic_info/
[5] (2006) http://news.softpedia.com/news/UV-Radiation-What-UVA-UVB-and-UVC-Rays-Are-and-How-They-Affect-Us-30345.shtml
[6] (2008) http://dermatology.about.com/od/skincancers/a/UV_radiation.htm
[7] http://www.skincancer.org/prevention/uva-and-uvb/uva-radiation-a-danger-outdoors-and-indoors
[8] http://dermatology.about.com/od/skincancers/a/UV_radiation.htm
[9] http://www.skincancer.org/prevention/uva-and-uvb/understanding-uva-and-uvb
[10] http://www.skincancer.org/prevention/uva-and-uvb/understanding-uva-and-uvb
[11] http://www.skincancer.org/skin-cancer-information/skin-cancer-facts
[12] http://dermatology.about.com/od/skincancers/a/UV_radiation.htm