Sunglasses do more than make us look good. They protect our eyes from short-term strain and discomfort as well as long-term damage such as blindness and eyelid skin cancer.
But just as sunglasses provide many different styles, they can also offer differing levels of protection from the sun. In this Q&A, Christina Cherny, OD, FAAO, an optometrist and an Instructor of Ophthalmology at the New York Eye and Ear Infirmary of Mount Sinai, explains what to look for in sunglasses.
Why is it important to wear sunglasses?
Sunglasses protect your eyes from the sun’s UVA and UVB rays. You should make sure you have sunglasses that protect 100 percent of UVA and UVB rays. These rays can cause damage to the eye. If you don’t wear sunglasses, you can develop eye cancer as well as cancerous and noncancerous growths on the outside of the eye, the eyelid, and around the eye. At the back of the eye, sunglasses can protect against macular degeneration and other conditions that can lead to blindness. Sunglasses can also slow the process of developing cataracts, which affect many people as we age.
How should I pick sunglasses?
Make sure the sunglasses provide 100 percent protection from UVA and UVB rays. Some inexpensive plastic ones don’t have UV protection, so they’re not helpful. You should get as dark a tint as possible; it doesn’t matter if the lens is brown, green, blue, or gray, as long as it is dark. Look for glasses with big lenses. Some people walk around with a tiny trendy sunglasses; these will protect the eyeball itself but not the skin around the eye or the eyelid. You should have good coverage.
What about polarized glasses and anti-reflective coating? Are those helpful?
Polarized glasses reduce glare, which is especially good if you are going to be boating or near water. Anti-reflective coating, too, can help reduce glare and help you see more clearly. You can get and anti-glare coating and polarized lenses in regular glasses as well as sunglasses.
Do mirrored sunglasses protect the eyes?
No. Mirrored sunglasses are just for fashion.
If I wear prescription glasses, should I also wear prescription sunglasses?
Yes. If you want to see clearly and protect your eyes, the two main options are wearing contact lenses under plain sunglasses or putting a prescription into your sunglasses. I’m also a big fan of clip-on sunglasses. I like the magnetic ones and traditional clip-ons. You should make sure that the clip-on sunglasses are UV protected.
Do you recommend transition glasses?
Transition glasses have lenses that look like regular lenses when you’re inside, but get darker when you go outside. The thing to keep in mind is that UV rays are what sets them off. So if you’re in a car where the windshield has UV blocker, the glasses aren’t going to change color. Transitions glasses also tend not to get as dark as regular dark sunglasses so they will not be as protective. They also take a few minutes to change, which can make it hard when you go from bright sunshine outside to a darker space indoors. As long as they’re UV protected, transition glasses are perfectly safe; they might just not be quite as dark or helpful as regular dark sunglasses.
How often should I replace my sunglasses?
Sunglasses don’t have an expiration date. But scratches make them less effective. If your sunglasses are scratched up, or if you have any questions, talk with your eye care professional.