When it comes down to dealing with the heavy dose of sunshine that summer brings, dark sunglasses are enough to protect your eyes, right? Ummm…no. Not all shades are created equal. That’s why we consider it our delightful duty to make sure you know about two of the superstars in the summer-lens category: UV-blocking and polarized lenses.

First of all, they aren’t the same. The lingo can get confusing, but like directions to the best burger joint in town, it’s something everyone should know. These terms often go hand-in-hand, but they have two different functions.

UV Lenses Lead the Radiation Smackdown

UV-blocking lenses stop the sun’s harmful ultraviolet (UVA and UVB) rays from reaching your eyes. Jeffrey Anshel, O.D., F.A.A.O., from Poinsettia Vision Center in Carlsbad, CA explains, “UV radiation can lead to abnormal eye growths, macular degeneration, general vision loss, and cancer of the eye.” (Ouch!)

Like we mentioned before, the darkness of your lenses has nothing to do with how much UV protection they provide. In fact, dark sunglasses without UV protection can actually be more dangerous because they cause your pupils to dilate, exposing your non-protected eyes to more UV rays.

Dr. Anshel advises, “When choosing sunglasses, be sure to ask your eye doctor or an optician to confirm that your lenses will have 100% UV protection from both UVA and UVB rays. As for contact lenses, some offer UV protection, but they don’t cover your whole eye.
I suggest wearing UV-blocking sunglasses in addition to UV-blocking contacts.”

Polarized Shades Keep You on Top of Your Game

While the goal of UV-blocking lenses is to protect your eyes, the point of polarized lenses is to remove glare so you can see more clearly and easily, i.e., less squinting! These lenses are a favorite among water sports enthusiasts, video gamers, and anyone who dislikes day-to-day glare.

Here’s how polarized lenses work. When light reflects off of surfaces such as lakes or cars, the light waves align in horizontal patterns, creating glare. The filters in polarized lenses block these horizontal waves, which (voila!) reduces glare. “If you want to check that your sunglasses are polarized,” says Dr. Anshel, “simply hold them in front of your face, look at your smartphone screen or any flat-panel computer display, and gently move your glasses up and down from right to left in a teeter totter motion. If the image disappears or you notice changes in brightness as they move, then your glasses are polarized!”

While glare reduction can be great, there are some circumstances in which it can actually be dangerous. If you’re skiing, snowboarding, or riding your motorcycle, you should not wear polarized lenses. Not being able to see icy snow on the mountain or wet pavement on the roads can lead to serious injury. Stick with your UV-blocking shades in these instances, and make sure your glasses/goggles are safety-approved!

The content of this article is for general informational awareness purposes only. Please consult your eye care doctor or physician for actual advice.