Sunglasses are fun and fashionable. But are your sunglasses protecting your eyesight from potential harm?
The sun emits both UVA and UVB radiation, year-round, and on both sunny and cloudy days. UVB rays are the ones that cause sunburn, and they can harm your eyes as well.
Just 30 extra minutes of UVB exposure per year can boost your risk of developing cataracts, a painless condition that causes blurred vision, by about 10 percent. New research indicates that UVA rays can be dangerous as well, linking them with malignant melanoma, the most deadly form of skin cancer.
Everyone is vulnerable to developing cataracts, even from minimal exposure to the sun. People from all walks of life should seek broad-spectrum protection from their eyewear.
Sunglasses are not just fashion accessories. Here are a few things to look for before you invest in a new pair of shades.
BEST COLOR. Exotic lens colors may be stylish, but gray—because it absorbs all colors about equally—diminishes color perception the least. Gray or smoke-colored lenses are best for depth perception, second best for color, and best suited for driving and other general use. Gray is also best for outdoor activities, such as golf, biking and tennis.
Green is the second-best choice when it comes to not diminishing color perception. Also, green works well in both low and bright light, making it great for daily wear. Brown gives the best color perception and helps filter out blue light, which makes it difficult to focus. Brown and amber are perfect for high-glare or hazy conditions.
PROTECTION. Sunglasses should block 99 percent to 100 percent of both kinds of ultraviolet radiation: UVA and UVB. Look for this information on a label or hangtag.
If glare is a problem, polarized lenses are a good choice. Mirror lenses also help decrease glare because they screen out more light than tinted lenses do.
Quality non-prescription sunglasses as those with lenses that are free of distortions, imperfections and mismatching of color and absorptive power.
To check the refractive quality of a lens, hold the glasses at arm’s length and look through each lens at a straight line or edge in the distance. If the line curves or appears distorted when you move the lens back and forth, the lens is optically imperfect.
Be protected with shatterproof sunglasses. Consider polycarbonate lenses, which are the most impact-resistant lenses available.
FRAME. If you often leave your glasses on your car seat or at the bottom of your purse, you’ll need to look for a sturdy frame, preferably one made of nylon (best for impact sports) or titanium (the strongest and lightest metal; great for everyday wear).
Plastic frames are good, too, and have a deep groove for the lens mounts, so the lenses aren’t likely to pop out. If you can’t tell what your favourite pair is made of, ask a salesperson.
LENS MATERIAL AND COATING. For scratch-resistance, glass is number one. Plastic scratches easily, but it’s durable and lightweight, making it a top choice. When considering eye protection, lens coating is key.
Polarized lenses filter out glare.
Mirrored specs reflect it back. For the most comfort in the sun, go with an antireflective coating on the back of the lenses. This ensure that any light coming in from the sides won’t bounce off the back of the lenses and irritate your eyes.