The Single Most Important Thing You Must Know About Your Sunglasses!

Summer means more time spent outdoors under a bright and powerful sun so a pair of sunglasses is a must! At Metrovision Optical Boutique we encourage our customers to wear their sunglasses all year round regardless of what season it might be or how many clouds are in the sky. Think of that overcast, gray June day when you ran out for just a few minutes and thought, “I don’t need my sunglasses or sunscreen.” But that’s the day when you get an unexpected and awful sunburn thanks to the deceptively high UV (Ultra Violet) index. The same principle holds true in the winter months when the glare from a day old snowstorm can be blinding. Ask a skier about how difficult it is to hit the slopes without their polarized sunglasses.

So when buying a new pair of shades the most important thing for the health of your eyes is to make sure the lenses are UV coated. The human eye has a built in mechanism of protecting itself. In dimly lit conditions the pupil opens wide while in brightly lit conditions, the pupil constricts. Pupil constriction can shield some of the harmful UV radiation bombardment reaching the inner eye…but not all of it. The thinning ozone layer has made UV exposure more intense. Plus the outer surfaces of the eye (cornea/conjunctiva) will only be protected as to how much you close your optical fissure (that’s a fancy way of saying “squinting”).

So placing a UV coated shield in front of the eye is the best most effective way of protecting the eye from UV radiation. Visible light reaching the eye is what enables humans to see. Any time you put a filter in front of the eye, it will, of course, decrease the amount of light reaching the eye. A tinted lens in front of the eye filters light. Sunglasses are the shield. Using a sunglasses lens that does not have this UV coating will mimic dimly lit conditions and cause the pupil to dilate (get larger) letting all those harmful, cataract-inducing UV rays to enter the inner eye. You would be better off wearing no sunglasses at all rather than a pair of non- UV-coated shades.

Luckily, most sunglasses have a UV coating, including all the models available at Metrovision Optical Boutique. Oh, one last tip. Do not wear your sunglasses at night no matter what a Corey Hart song from the 1980s tells you!

If you’re in the market for a new pair of sunglasses schedule an appointment with us and come back here next week for some expert tips on selecting your new set of shades!