Most of us wear sunglasses for two reasons and two reasons only: To quit squinting and to look suave as heckin’ heck. But there’s one even better reason to wear sunglasses, according to Christopher Quinn, O.D., president of the American Optometric Association: To not go completely blind.
“People can experience both short-term and long-term damage to their eyes from ultraviolet exposure [that is, harmful electromagnetic radiation put out by the sun],” Quinn warns. “When eyes are exposed to excessive amounts of UV radiation over a short period of time, they’re put at risk for photokeratitis, or sunburn of the cornea—symptoms of photokeratitis include red eyes, a foreign body sensation or gritty feeling in the eyes, headache, extreme sensitivity to light and excessive tearing.” Photokeratitis can also result in temporary vision loss, but the condition is typically reversible within one or two days, and it rarely causes permanent damage.
On the flip side, never wearing sunglasses can (and will) ruin your eyes for life. “The longer the eyes are exposed to UV radiation, the greater the risk of developing conditions like cataracts [clouding of the eye lense], macular degeneration [deterioration of the retina] or, in some cases, skin cancer around the eyes,” Quinn explains. In fact, the Skin Cancer Foundation reports that as many as 10 percent of all skin cancers are found on the eyelids.
Now that you’re frantically shopping for sunglasses online, prepare to shop ‘til you drop. “Some people only think about sun protection when they spend a day at the lake, beach or pool, but sun exposure adds up day after day,” Quinn says. “On an overcast day, nearly one-third of solar radiation reaches the earth, so it’s important to wear sunglasses whenever you’re outside.”
Not all sunglasses provide ample protection against the elements, though: The lenses on your sunglasses should block out 99 to 100 percent of both UVA and UVB radiation, and should screen out 75 to 90 percent of all visible light, according to Quinn. So while it’s fine and good to shop for sunglasses that’ll make you look like James Dean, be sure they’ll protect your eyes, too.