See the Light: Protecting Your Eyes from the Sun

Sunscreen may be the first thought that comes to mind when you think of protection against the summer sun. But after slathering it on your face, remember to top it off with sunglasses and/or a hat. Your eyes also need shielding from the sun's harmful rays.

"The best protection for your eyes is a pair of sunglasses that block 99 percent of both types of ultraviolet (UV) rays, UVA and UVB," says Christina Moon, MD, Director of Cornea and Refractive Surgery in the Division of Ophthalmology at Beth Israel Deaconess Medical Center. "Wraparound sunglasses give your eyes additional protection on the sides, and wide-brimmed hats are also helpful in shielding your eyes from the sun, because not all light comes to you directly."

Humans have a wide field of vision — notice how much you can see just by keeping your head still and moving your eyes around — so UV light can reach your eyes from many angles. A significant portion of UV exposure actually comes from light reflecting off water and sand, or snow and ice, meaning UV-blocking lenses and sunscreen are just as important in the winter as in the summer.

"Wearing sunblock on the face helps protect your eyes from reflected and indirect light in the areas that your sunglasses or ski goggles don't cover," Dr. Moon adds.

While We're Young

Sunglasses and ski goggles aren't just for adults. Kids need eye protection, too. Though eyesight tends to worsen as we age, about 50 percent of actual eye damage occurs before the age of 18.

"The natural lens in your eye blocks out more UV light as you get older," Dr. Moon says. "So the younger you are, the more important it is to protect your eyes from UV rays."

Swimming goggles with UV protection are available for use in the pool or the ocean to help cut down direct and reflected light. For other sports, using UV-protected eyewear is also advisable, both to protect eyes from sun exposure and to help prevent sports-related injuries.

The American Optometric Association recommends that children with no symptoms of eye problems should have a general eye exam every two years, beginning around age 6. Adults should have a dilated eye exam every one to two years, and annually after the age of 60, or as recommended by your doctor due to your medical history.

Dermatologists tell kids and parents alike that your skin still needs sun protection even when it's overcast, and the same goes for your eyes. UV rays do penetrate clouds and sometimes reflect off clouds.

"You can get as much, or even more, sun exposure on an overcast day than you can on a bright day," Dr. Moon says. "What's also interesting about the eyes is that the times during the day when the most UV light can get into the eyes — no matter the weather — are actually before and after that 10 a.m. to 2 p.m. period when the sun's rays are said to be at their strongest. Light reflects the most between 8 and 10 a.m., and also 2 and 4 p.m., so those are the times when you should especially be aware of protecting your eyes."

Avoiding Eye Troubles

Several eye conditions, most notably one form of cataracts, have been attributed to frequent and long-term exposure to UV light.

"Cataracts occur when the eye's lens becomes cloudy because of cell damage, and they typically occur in older people," Dr. Moon explains. "But, studies have shown that cataracts are more likely to develop at a younger age in people who spend a lot of time outdoors and use little to no UV protection."

Other eye conditions linked to prolonged UV exposure that Dr. Moon and her colleagues tend to see include cancers of the eye and eyelid (basal and squamous cell carcinomas as well as melanoma), and benign ailments such as pterygium and photokeratitis.

Pterygium is a growth in the eye that is not usually serious, but can lead to irritation and blurred vision. It typically grows slowly over several years and eventually stops. In more severe cases, the lesion can continue growing over the pupil and further interfere with eyesight.

Photokeratitis, also known as "snow blindness" due to the way light reflects off snow and ice, can occur after being exposed to a lot of UV radiation in a short period of time. It can cause temporary sensitivity to light and often goes away on its own, though it sometimes results in damage to the cornea.

Dr. Moon also cautions that "UV exposure" doesn't just refer to being outside.

"Many people are exposed to UV radiation by using tanning beds and other man-made sources of ultraviolet lights, like in laboratory work or occupations like welding," she says. "UV-blocking eyewear should always be worn in these situations as well. Some contact lenses now have UV protection, but keep in mind that that protection doesn't extend to the eyelids or the conjunctiva (a thin membrane that covers the inside of the eyelid and the white part of the eye). You want to be wearing something that covers the whole eye, or as much of the eye as possible."

Above content provided by Beth Israel Deaconess Medical Center. For advice about your medical care, consult your doctor.

Posted July 2015