How to buy the best shades

One summer, my husband and I were vacationing on the Jersey Shore. In one of the shops near the beach, I found a really cool pair of super-dark sunglasses. They must have been polarized too, because they made the clouds look bright white and crisp against the blue sky. At the time, I thought those dark glasses would better protect my husband’s eyes from the sun. Now I know that’s not true.

In fact, ophthalmologists say dark-tinted lenses may actually let more damaging ultraviolet (UV) waves into the eye, because dark lenses keep us from squinting and our pupils don’t constrict as they would in bright light. The experts say it’s not the shade of the lenses but the protection they offer that’s important when picking out sunglasses. They recommend buying sunglasses that offer 100 percent protection from UVA and UVB rays.

Jason Yam, M.D., an ophthalmologist at The Chinese University of Hong Kong, said that the eye, like the skin, absorbs UV light. Shorter wavelengths — the more dangerous ones — are caught by the cornea, and longer wavelengths potentially reach the lens and retina. Experts are at odds on how much, if any, damage these rays do to our eyes. Most agree that it’s better to err on the side of caution and wear UVA- and UVB-rated sunglasses.

But a few go as far as saying we shouldn’t wear sunglasses at all. They argue that our bodies do what they’re supposed to do when we’re in bright sunlight. Our eyes squint and the pupils constrict, which, they claim, is part of good eye health. As for whether or not sunglasses should be polarized, that’s up to the buyer. Polarization helps deflect glare but does nothing to block those bad rays. So go ahead and buy those cool shades, but look for ones with the UVA and UVB guarantee.

For more, go to:

http://www.medpagetoday.com/Ophthalmology/GeneralOphthalmology/40290