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UVA and UVB Rays

What's the Difference Between UVA and UVB Rays?

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Steve Wisbauer/Getty

Steve Wisbauer/Getty

Steve Wisbauer/Getty

The rays that come from the sun, UVA and UVB rays, are well known to cause damage to our skin. From early aging all the way to skin cancer, there are many reasons to protect yourself from the sun's rays.

But before you think you know enough just because you apply sunscreen, think again! Knowing the difference between UVA and UVB rays can help you pick out the best sunscreen for you and give you insight into just what each ray is responsible for.

UVA Rays

UVA rays are constantly present, no matter the season or the weather. If you think you can't get sun damage on a cloudy day, tell that to the UVA rays. They are so powerful that they also penetrate some clothing and even glass. (When was the last time you applied sunscreen before getting behind the wheel?)

UVA rays used to be considered relatively safe, in terms of the sun's rays, and that's why tanning beds, which use UVA rays, took center stage. But we now know that using tanning beds before the age of 30 can actually increase your risk of skin cancer by 75%!

Also UVA rays are the rays responsible for the signs of aging because they are able to penetrate much deeper into the surface of the skin, damaging the cells beneath.

While people think their skin looks younger because it's tan, the reality each, each tan is giving your skin irreversible damage, and you will see it's damage later in life.

When you think of UVA rays, think sun spots, leathery skin and wrinkles.

UVB Rays

UVB Rays are the rays you can blame when you get a sunburn. Unlike UVA rays, these rays aren't always the same strength year round - They're more prevalent in the summer months, however they are able to reflect off of water or snow, so it's always important to protect yourself year-round.

UVB rays are responsible for causing most skin cancers. While large doses of UVA rays can contribute to cancer, it's the UVB rays that are commonly to blame.

If you've heard the advice to stay out of the sun though the mid day hours, it's the UVB rays you're trying to avoid. They are most prevalent mid day, so if you must be out at that time, protect your skin.

When you think of UVB rays, think sun burn and cancer.

How to Protect Your Skin

All sunscreens protect against UVB rays, but it wasn't until recent years that sunscreen started including UVA protection. And in fact, not all sunscreens do. Look for one that specifically says UVA/UVB or "broad spectrum coverage" on the bottle.

Use a minimum of SPF 15 and reapply every hour or two at the very most. To see how long your sunscreen will last under perfect conditions, take the number of SPF and multiply it by 10. That is the length of time you'd be safe from the sun's rays. (In perfect conditions - No water or sweating taken into account here.)

For example: SPF 20 x 10 = 200 minutes of sun protection

If you're looking for sunscreen options, these might help.

Don't forget, sunscreen doesn't last forever! You should be using approximately a full ounce on your body and about 1 teaspoon on your face each time you apply.

Don't let a cloudy day affect your decision to protect your skin from the sun's damaging rays. The less you protect your skin, the more prone you are to sunburn, cancer and aging signs.

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