Understanding UV Rays…
The sun is becoming a “hot” topic these days as more and more people put sunscreens under scrutiny. Most of this controversy stems from the UV rays that the sun emits. The sun emits three different types of rays: UVA (long-wave), UVB (short-wave), and UVC, which never penetrate the ozone.
Our understanding of exactly what kinds of damage UV rays cause the skin, and how best to protect ourselves, seems to shift every year as new research comes out. For example, it was once thought that only UVB was of concern, but we keep learning more and more about the damage caused by UVA.
UVA rays (Aging Rays)
We are exposed to UVA rays at an equal intensity throughout the day and all year round. This type of sun ray accounts for 95% of the UV radiation reaching the Earth’s surface, and can penetrate clouds and glass.
The sun is becoming a “hot” topic these days as more and more people put sunscreens under scrutiny. Most of this controversy stems from the UV rays that the sun emits. The sun emits three different types of rays: UVA (long-wave), UVB (short-wave), and UVC, which never penetrate the ozone.
Our understanding of exactly what kinds of damage UV rays cause the skin, and how best to protect ourselves, seems to shift every year as new research comes out. For example, it was once thought that only UVB was of concern, but we keep learning more and more about the damage caused by UVA.
UVA rays (Aging Rays)
We are exposed to UVA rays at an equal intensity throughout the day and all year round. This type of sun ray accounts for 95% of the UV radiation reaching the Earth’s surface, and can penetrate clouds and glass.
UVA rays penetrate the skin more deeply than UVB rays, which plays a major part in skin aging and wrinkling. UVA damages skin cells called keratinocytes in the basal layer of the epidermis, where most skin cancers occur. (Basal and squamous cells are types of keratinocytes.) UVA contributes to and may even initiate the development of skin cancers.UVA is the dominant tanning ray, and we now know that tanning, whether outdoors or in a salon, causes cumulative damage over time. A tan results from injury to the skin’s DNA; the skin darkens in an imperfect attempt to prevent further DNA damage. These imperfections, or mutations, can lead to skin cancer. The high-pressure sunlamps used in tanning salons emit doses of UVA as much as 12 times that of the sun. Not surprisingly, people who use tanning salons are 2.5 times more likely to develop squamous cell carcinoma, and 1.5 times more likely to develop basal cell carcinoma. According to recent research, first exposure to tanning beds in youth increases melanoma risk by 75 percent.
UVB Rays (Burning Rays)
UVB, the chief cause of skin reddening and sunburn, tends to damage the skin’s more superficial epidermal layers. Its intensity varies by season, location (greater by the equator and high elevations), and time of day. The most significant amount of UVB hits the U.S. between 10 AM and 4 PM from April to October. 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 85 percent of the rays. Going outside in the winter after a fresh snowfall means you’re getting twice the amount of sun rays to your skin! That’s damaging your skin twice as fast!!!
Protection Your Skin!
Protect yourself from UV radiation, both indoors and out. Always seek the shade outdoors, especially between 10 AM and 4 PM. Don’t forget that UVA penetrates glass, so you are still exposing yourself to dangerous UV rays when driving or sitting by windows.
Outdoors, dress to limit UV exposure: Special sun-protective clothes with UPF (ultraviolet protection factor) indicate how much UV radiation can penetrate the fabric; the higher the UPF, the better. A shirt with an UPF of 30, for example, means that just 1/30th of the sun’s UV radiation can reach the skin. Bright- or dark-colored, lustrous clothes reflect more UV radiation than do pastels and bleached cottons; and tightly woven, loose-fitting clothes provide more of a barrier between your skin and the sun. Finally, broad-brimmed hats and UV-blocking sunglasses help shield the sensitive skin on your head, neck, and around the eyes — areas that usually sustain a lot of sun damage. Sunglasses are our eyes only protection from the sun harmful rays. UVB rays have also been known to cause cataracts and melanoma on the iris.
UVB, the chief cause of skin reddening and sunburn, tends to damage the skin’s more superficial epidermal layers. Its intensity varies by season, location (greater by the equator and high elevations), and time of day. The most significant amount of UVB hits the U.S. between 10 AM and 4 PM from April to October. 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 85 percent of the rays. Going outside in the winter after a fresh snowfall means you’re getting twice the amount of sun rays to your skin! That’s damaging your skin twice as fast!!!
Protection Your Skin!
Protect yourself from UV radiation, both indoors and out. Always seek the shade outdoors, especially between 10 AM and 4 PM. Don’t forget that UVA penetrates glass, so you are still exposing yourself to dangerous UV rays when driving or sitting by windows.
Outdoors, dress to limit UV exposure: Special sun-protective clothes with UPF (ultraviolet protection factor) indicate how much UV radiation can penetrate the fabric; the higher the UPF, the better. A shirt with an UPF of 30, for example, means that just 1/30th of the sun’s UV radiation can reach the skin. Bright- or dark-colored, lustrous clothes reflect more UV radiation than do pastels and bleached cottons; and tightly woven, loose-fitting clothes provide more of a barrier between your skin and the sun. Finally, broad-brimmed hats and UV-blocking sunglasses help shield the sensitive skin on your head, neck, and around the eyes — areas that usually sustain a lot of sun damage. Sunglasses are our eyes only protection from the sun harmful rays. UVB rays have also been known to cause cataracts and melanoma on the iris.
Using these guidelines a little common sense will help to decrease your risk of skin cancer.
Stay tuned for our next topic…SPF factors and what they protect!
Stay tuned for our next topic…SPF factors and what they protect!
0 comments:
Post a Comment