What's the difference between UVA and UVB?
Ultraviolet A (UVA) rays make the skin tan; ultraviolet B (UVB) rays cause skin to burn. UVB used to get all of the blame for causing skin cancer, but new research shows UVA is equally damaging. This is particularly worrisome since UVA rays are 30 to 50 times more prevalent, and they penetrate deeper into skin cells.
What does SPF stand for? Is a higher number more effective?
An SPF, or sun protection factor, indicates a sunscreen's effectiveness at preventing sunburn. How do you know which SPF to choose? If your skin reddens in 10 minutes without sunscreen, SPF 15 multiplies that time (10 minutes) by 15, meaning you'd be protected from sunburn for approximately 150 minutes or 2 1/2 hours.
Of course, this depends on an adequate application of sunscreen and is based on SPF calculations with artificial instead of natural sunlight.
It is recommended to use sunscreen with at least SPF of 15, which blocks 93% of UVB rays. Higher SPFs provide a greater protection, but only to a certain point. SPF 30 blocks 97 percent of UVB and SPF 50+ blocks 98 percent.
Don't forget to protect your eyes!
Just like our skin, the sun can also damage our eyes. Although designed to protect the eye, the eyelid’s skin is thin and contains many fragile tissues vulnerable to UV light. Inside the eye, the lens and cornea, both transparent, filter UV rays, but years of UV absorption can damage them. The lens, the eye’s focusing mechanism, can turn yellowish and cataractous. The cornea, the area in front at the outer layer of the eye, admits light and images to the retina.*
UV radiation can increases your odds of getting cataracts, which cloud the eye’s lens and lead to diminished eyesight. It has also been linked to macular degeneration, a treatable, but incurable disease of the macula, a part of the retina that is essential for sharp vision.
How to reduce damage from UV rays
Fortunately, like your skin, there are easy ways to protect your eyes such as wearing sunglasses or wide brimmed hats when in the sun. What a great excuse to purchase some hot summer accessories!
With over 25 years experience licensed optician Joe Bushara and his highly experienced team, bring you the latest trends in frames and technologies in lenses from around the world.