UV Light and Your Eyes: Can Sun Glare Damage Your Vision?
Summer is heating up, and the sun is at its most intense. While you cover yourself in sunblock, don’t forget about UV light and your eyes, and the potential for sun damage.
By Carter Liotta, OD, Vision to Learn
The days are long and the sun is more intense, and most people don’t think twice about wearing sunblock and broad hats. But are you forgetting sunglasses? While UV light can cause long-term problems in the eye, like cataracts and macular degeneration, people rarely understand that the eye’s surfaces can suffer their own, unique forms of sunburn.
What is UV light?
When people speak of “ultraviolet light,” they’re speaking of ultraviolet radiation—an invisible form of high-energy ray on the electromagnetic spectrum. There are three types:
- UVA rays pass through the cornea, or outer surface of the eye, and cause cataracts and retina problems.
- UVB light, responsible for wrinkles and skin cancer, can cause pinguecula, and photokeratitis.
- UVC light, filtered by the atmosphere, is the most damaging but little cause for concern.
Various factors impact the effects of UV radiation. These include:
- Altitude. UV radiation is stronger at higher altitude.
- Geographic location. UV radiation is greater near the equator.
- Time of Day. From 10 AM to 2 PM, the sun’s rays are strongest.
- Medications. Birth control pills and certain antibiotics can increase UV sensitivity.
Is UV light bad for your eyes? UV light damage
The most common short-term sun-related eye problem is photokeratitis (sometimes called UV keratitis or snowblindness). Similar to sunburn, the sun can damage the cornea (the clear dome-shaped part of the eye where a contact lens sits). Staring into the sun for lengthy periods of time, as when viewing an eclipse, is a culprit. So, too, is reflected sun from snow, sand, water and ice.
The most frequent symptom of UV keratitis is pain and redness. Other symptoms include:
- Gritty feeling in the eyes
- Light sensitivity
- Blurry vision and tearing
- Lid twitching
- Visual halos
Long-term damage from UV light.
Farmers and other outdoor workers are at high risk for UV light damage. Besides photokeratitis, UV light can cause long-term problems:
- Pinguecula is a yellow-white bump that forms next to the cornea, on the conjunctiva—the clear tissue atop the “whites of your eyes.” It is common and non-cancerous, but some patients present with cosmetic concerns.
- Pterygium is a benign wedge-shaped growth atop the conjunctiva that has its own blood vessels and may grow over the cornea and cause problems.
- Cataracts are a clouding or yellowing of the eye’s lens, which sits behind the colored part of the eye. When cataracts become symptomatic and impact quality of life, patients must have surgery to remove them.
- Macular Degeneration is a permanent, degenerative condition that causes blindness in the center of vision. Though UV light is not the sole cause, it is a factor.
UV Light Eye Protection
Glasses with UV coating are your best defense against UV radiation. Think not only of sunglasses: clear prescription lenses often block UV rays. Your eye care professional can help you select appropriate lenses.
Larger glasses offer better protection, and wrap-around performance or sport sunglasses are best. That broad-brimmed hat? It can reduce UV eye exposure as much as 49%!
UV Glasses for Computer Use?
With everybody using computers and tablets, patients sometimes wonder if their devices are causing UV damage. Old TVs and monitors that use tubes emit low levels of UV radiation. LCD monitors found in laptops, TVs, monitors, smartphones and tablets do not emit UV light at all. Unless your phone is reflecting sunlight into your eyes, you have no cause for concern!
There’s no reason to avoid the beach or the boat, the sand or the slopes. Just remember: think about UV light and your eyes—not just your skin.