The Washington PostDemocracy Dies in Darkness

The Big Number: UV ratings for sunglasses

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Not only can the sun’s ultraviolet (UV) rays harm your skin, but they can damage your eyes as well. For protection, says the American Academy of Ophthalmology, wear sunglasses that block 99 to 100 percent of both UVA and UVB rays. Retailers say that requires a rating of UV400 or higher. Over time, sun exposure can increase your chances of developing eye disease — cataracts, growths on the eye, macular degeneration and even a rare form of cancer, ocular melanoma, according to the academy. In addition, eye “sunburn” — known as photokeratitis — can stem from short-term exposure to UV rays, especially when reflected off the water or sand (or, in the winter, off snow or ice). Blurry vision and sensitivity to bright light can result. What else should you do for your eyes’ sake? Wear oversize or wraparound sunglasses, or don a wide-brimmed hat. Make sure kids have UV-protected sunglasses, too. And, don’t focus on the color of the lenses, because darker lenses do not automatically block more UV rays: It’s the number, UV400, that makes a healthy difference.

— Linda Searing

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