The ABCs of SPF
Aug 02, 2012 06:34PM
● By Anonymous
SPF—Sun Protection Factor: a rating for the degree of protection provided against ultraviolet B (UVB) rays by sunscreens. (Specifically, that means that if you can stay out in the sun without burning for, say 30 minutes, a product with an SPF rating of 15 will allow you to be exposed to the sun 15 times longer than that without burning. Of course that’s providing you lather up thoroughly and don’t sweat or move.)
UVB: ultraviolet radiation from the sun, with relatively short wavelengths, is associated with sunburn, darkening and thickening of the outer layer of the skin, and melanoma and other types of skin cancer.
UVA: ultraviolet radiation from the sun, with relatively long wavelengths, may not cause a visible sunburn, but they can still damage and wrinkle the skin, and they penetrate deeper into the skin that UVB.
Broad Spectrum Sunscreen: Recommended by the U.S. Environmental Protection Agency, broad spectrum sunscreens protect against both UVA and UVB rays.
Five myths about sun exposure:
Nothing higher than SPF 30 works.
Experts often question whether anything above SPF 30 is really needed. A sunscreen with an SPF of 15 provides 93 percent protection from harmful UVB rays, while a sunscreen with SPF 30 provides 97 percent protection. Therefore, if we are protected against 93 percent of harmful rays, what is the point of using a higher SPF? The truth is a higher SPF can’t hurt. It may even be helpful to those who do not use enough sunscreen in the first place or to those who do not apply it often enough.
SPF 15 + SPF 25 = SPF 40
Talk about fuzzy math. Unfortunately, it doesn’t quite work this way. When applying sunscreens with different degrees of protection, the highest SPF is actually the only one that works. Therefore, SPF 15 + SPF 25 = SPF 25. Sorry!
I can’t get sunburned on cloudy days or in the winter.
This is probably one of the biggest misconceptions. Even on the coolest or cloudiest of days, harmful rays can break through. In fact, up to 80 percent of the sun’s ultraviolet rays can pass through the clouds to your skin. And ever wonder why you get sunburn when you are skiing down the slopes in December? Well, the snow reflects 80 percent of the sun’s UV rays, which actually increases your need for sunscreen.
If I have darker skin I don’t need sunscreen.
People with darker skin colors may not burn as easily or obviously, but they are also at-risk for skin cancer. Everyone is at risk of skin cancer. One in five Americans will develop skin cancer, and one person dies from this disease every hour, according to the EPA.
Putting on sunscreen once a day is enough.
Not only do people not apply sunscreen often enough, they don’t apply enough of it. The EPA says sunscreen should be reapplied every two hours, or after swimming or sweating. Additionally, sunscreen should be applied 15 minutes before going out in the sun and to dry skin. When it comes to how much sunscreen to apply, dermatologists recommend one ounce, which is approximately the same amount as a shot glass, or an amount sufficient to cover the exposed areas of your body. (Of course adjust amount upwards based on body size and the skimpiness of the bikini.) Usually, people only apply between 25 and 50 percent of the amount they should. And remember the nooks and crannies. Coating arms, legs, shoulders and noses is important, but don’t forget ears, bald spots and scalps, top of feet, and your lips. There are special high SPF balms made just for our lips.