9 things to know about sunglasses, eye protection and cancer

You’ve put on your UPF-rated clothing, applied your sunscreen and positioned your beach umbrella carefully. But are you also wearing sunglasses to protect your skin and eyes from the sun’s harmful UV rays, which can cause both skin cancer and eye cancer?

These wardrobe staples aren’t just for keeping a low profile or making a fashion statement. UV-rated sunglasses can also provide critical daily protection for your eyes and the sensitive skin around them. 

So, what should you look for when shopping for sunglasses? How do you know if they offer enough UV protection? And, are some lens colors better — or more protective — than others?

We went to dermatologist Valencia Thomas, M.D., director of MD Anderson’s Dermatology and Mohs Center. She answered these and six more questions about sunglasses and eye protection.

Do all sunglasses protect your eyes from ultraviolet (UV) rays?

No. Some are just colored plastic. Look for a sticker or tag that says UV400 or UV 95-100%. This is the highest level of ultraviolet protection currently offered in sunglasses.

Are sunglasses without UV protection harmful?

Yes. Sunglasses without UV protection allow harmful UV rays to reach the skin of the eye, the front of the eye and deep inside the back of the eye.

Furthermore, because sunglasses artificially darken the environment and allow your pupils to dilate, even more harmful UV rays can reach the back of the eye than they normally would if you were not wearing sunglasses.

That's why it’s so important to look for UV protection in sunglasses, especially when other features are being emphasized, such as polarized sports models that decrease eye strain.

Does ‘polarized’ mean the same thing as ‘UV protection?’

No. Polarized lenses only reduce glare, or the brightness of reflected sunlight. That’s why if you look down into a river or lake with polarized glasses on, you can often see what’s going on beneath the surface. UV protection is entirely different.

Are designer sunglasses any better than the cheap ones at the drugstore?

No, not from a protection standpoint. Designer sunglasses may be a lot cuter and trendier, but you don’t have to buy expensive sunglasses to get good UV protection. Just look for the sticker that says UV400 or UV 95-100%.

Are certain colors of sunglasses considered better than others?

Yes. Yellow-colored lenses don’t offer as much protection as grey or brown-tinted lenses do. 

Do transitional lenses offer UV protection, too?

Lenses that automatically darken when exposed to bright light and become clear under darker conditions may offer UV protection, but not always. So, talk to your retailer to confirm the details about your specific lenses.

Do I need a wraparound style of sunglasses for maximum protection?

No. Many different styles of glasses offer good UV protection. You don’t necessarily need a wraparound style.

That being said, there’s no such thing as eyelid sunscreen. So, you should not be applying sunscreen to your eyelids or anywhere else inside the bony orbit, or eye-socket area. That’s why we rely on sunglasses and hats to shield our eyes. You don’t want to introduce any irritants there.

Which eye and eyelid cancers are associated with UV exposure?

Basal cell carcinomas are the most common type of cancer caused by UV exposure. One study out of Australia estimated that about 90% of malignant tumors on the eyelid were basal cell carcinomas. You can also get melanoma on your eyelid.

But eyelid cancers are very different from those that develop in the eyeball itself. Ocular melanomas — or those associated with the eye socket — can be further subdivided into four different categories: uveal, conjunctival, eyelid and orbital. Eyelid melanomas have been associated with UV exposure, but there is limited data associating other forms of ocular melanoma with UV light.

How else can UV exposure negatively affect your eyes?

Cataracts

About 20% of cataracts are thought to be caused by UV exposure. Cataracts can get worse over time and diminish your vision, so they often have to be removed surgically.

Pterygium

Pronounced “tur-RIDGE-ee-yum,” this is when a section of the epithelial — or top — layer of your eyeball gets thick, yellow and overgrown. It’s completely unrelated to jaundice, which is a temporary discoloration of the eyeball caused by digestive problems. Pterygium may also obscure your vision and can be treated with surgery or steroidal eyedrops. It’s sometimes called “surfer’s eye.”

Photokeratitis

This is when the eyeball itself gets “sunburned.” It’s a very painful condition and needs professional evaluation. But it usually resolves on its own within a few days, using some combination of pain relievers, antibiotics, lubricants and ointments. It shouldn’t affect your vision immediately, but it may cause problems later on, such as corneal degeneration.

The most important thing to remember is that none of these conditions occur right away. All of them happen very gradually, over time. But you can prevent or delay them by wearing UV-rated sunglasses and keeping your eyes lubricated.

Request an appointment at MD Anderson online or call 1-877-632-6789.