Why People Need Sunglasses
We often buy sunglasses the same way we buy fashion accessories: a new pair every spring with an emphasis on fashion over function. But, being in the sun should always mean taking precautions against damaging ultraviolet (UV) radiation.
The American Optometric Association suggests you shop smart. When making that fashionable purchase, remember sunglasses protect your eyes. So, how well they work matters just as much as how they make you look.
The sun’s UV radiation can cause cataracts; benign growths on the eye’s surface; cancer of the eyelids and skin around the eyes; and photokeratitis, sometimes called snow blindness, which is a temporary but painful sunburn of the eye’s surface. Wide-brimmed hats and caps can block about 50% of UV radiation from the eyes, but optometrists say that is not enough protection.
Long-term exposure to the blue and violet portion of the solar spectrum has been implicated as a risk factor for macular degeneration, especially for individuals who are “sun sensitive.”
Buying Lenses: What to Look for to Ensure Protection
You should wear sunglasses outdoors whether you are working, driving, participating in sports, taking a walk or running errands.
- Don’t be misled by faulty UV claims. To make sure that UV labels are accurate, buy sunglasses where there is equipment available to check the lenses’ UV protection capabilities, or ask your optometrist for his or her opinion on a specific purchase.
- Check lenses to be sure the tint is uniform, not darker in one area than another. With gradient lenses, the tint should lighten gradually from top to bottom. Sunglass tints used for driving should be gray to allow proper traffic light recognition.
- Ensure that lenses are distortion free. Hold the glasses at arm’s length. Look through them at a straight line in the distance. Slowly move the lens across the line. If the straight edge distorts, sways, curves or moves, the lens has imperfections.
- To be sure the lenses block enough light, try them on in front of a mirror. If you can see your eyes easily through the lenses, they probably are not dark enough. Note: this test does not apply to photochromic (light-sensitive) lenses.
- At a minimum, look for sunglasses that: Block at least 99% of both UV-A and UV-B radiation. Screen out 75% to 90% of visible light. Are gray for proper color recognition and free of distortion and imperfection.
- Certain contact lenses can provide additional UV protection; ask your optometrist for more information.
Content courtesy of AOA.org