Ultraviolet Radiation and Your Eyes



Most people are aware of the skin cancer risks associated with too much ultraviolet (UV) light exposure. It’s why we carefully apply sunscreen before heading out the door. But did you know that it’s just as important to protect your eyes? Research shows that more than one-third of adults have experienced symptoms due to prolonged UV exposure, such as eye irritation, trouble seeing and red or swollen eyes.

The good news is that protecting your eyes is as easy as protecting your skin. Here’s what you need to know.

What Is UV?

The sun emits different types of UV rays—two of which are widely known to be a serious cause for concern. In particular, UVA and UVB are not fully absorbed or altered when they pass through the atmosphere, which means they pose a risk to eyes and skin. How much of a risk depends on lots of factors, including your geographic location (UV levels are greater in tropical areas near the earth's equator), altitude (UV levels are greater at higher altitudes) and time of day (UV levels are typically greater from 10 a.m. to 2 p.m.).

Other factors that influence risk include medications you take and your specific setting. For example, if you are in an environment with lots of highly reflective surfaces, such as sand and snow, UV exposure is much higher than it would be if you were standing in middle of a city, shaded by lots of tall buildings.

Surprisingly, seasonal changes have less of an impact than you might think. In fact, even though you feel the sun’s rays more in the summer, because snow is so reflective, winter can be twice as dangerous.

Why Are Eyes at Risk?

Although UV comes from the sun, make no mistake: it has a dark side—particularly with regard to the health of your eyes. Several eye problems have been linked to UV exposure, including cataracts, macular degeneration, pingueculae, pterygia, photokeratitis, cancers of the eye and surrounding skin, and more.

  • Cataracts. The World Health Organization (WHO) estimates that up to 20 percent of all cataract cases are attributable to UV radiation and are preventable.1

  • Macular degeneration. Age-related macular degeneration (AMD) is the leading cause of blindness in adults 60 and older, but higher UV exposure at an earlier age has been significantly associated with early AMD.

  • Pingueculae and pterygia. These visible growths on the eye's surface can cause corneal problems and distort your vision.

  • Photokeratitis. Also known as snow blindness, photokeratitis is like a sunburn on your cornea. This painful inflammatory state causes temporary vision loss.

Many people had no idea how much damage they were sustaining in their younger years. Indeed, UV exposure is cumulative over your lifetime, meaning you can’t turn back time and undo skin or eye damage that’s already occurred. However, you can lessen your risk of making it worse. And, if you’re young or have little kids, take advantage of your good fortune and start to increase your protection from the sun now.

How to Stay Safe?

Think of it this way: sunglasses are to eyes what sunscreen is to skin. Sunglasses are your eyes’ best defense against dangerous UV rays. That being said, not all sunglasses offer suitable protection, so check labels or bring them to your eye doctor to be checked out. You want to make sure your shades block 100 percent of UV rays.

With regard to the color of your sunglass lenses, you might be surprised to learn that this has virtually no effect on the amount of UV protection. Whether they are amber, grey, or brown matters less than the built-in UV protection each provides.

On the other hand, frame style does play a role. Close-fitting and wraparound styles offer better protection because fewer rays can peak in through the sides of the frames. Similarly, a wide-brimmed hat can offer additional shield and therefore another layer of protection.

It’s also important to recognize that you need to protect your eyes even when conditions are overcast. Remember, even in winter, reflected UV is dangerous. Likewise, in the summer, rays reflected from buildings, sand and lakes can be a hazard.

This post originally appeared on Cooper Vision.