By Jennifer DeLeo

While sunglasses have always been a fashion statement – from cool aviators to the large frames worn by celebrities – they are also a must if you are out in the sun for long periods of time.

We know that overexposure to the sun is bad for our skin – did you know it can also be harmful to your eyes?

"Bright light itself on a sunny day in the short term doesn't pose any risk to the eye. The eye is really constructed to deal with short term," says ophthalmologist Mark Blecher, MD, of Wills Eye Institute, which also serves as Jefferson's Department of Ophthalmology. But prolonged exposure to ultraviolet rays, he explains, can damage the cornea, lens and retina of the eye either temporarily or worse – permanently.

Some of the risks are:

• Cataracts, a clouding of the lens of the eye
• Eyelid sunburns
• Photokeratitis, a burn to the cornea
• Pterygia, a benign growth on the white of the eye
• Skin cancer, including the eyelids
• Solar retinopathy, a burn to the retina

The best way to shield your eyes

The best way to shield your eyes from the sun is to wear UV-protected sunglasses. When picking out a pair, don't be fooled by the darkness of the lens; check to make sure that they are labeled "UV 400" or "100% UV Protection." And if those sunglasses wrap all the way around the temples, even better.

Just because you may have darker skin or eyes, doesn't mean you don't need to wear sunglasses. Jefferson ophthalmic plastic surgeon Nancy G. Swartz, MS, MD, FACS, says that "if you have dark skin and eyes, you still need to wear sunglasses. Although your skin may offer protection from skin cancer and premature aging, your risk of eye damage is no different than the risk of someone with fair skin."

"Ultraviolet rays know no season," Dr. Blecher says. He recommends wearing UV-protected sunglasses all year round, not just during the summer months and especially while you're at the beach or at higher elevations. The risk of eye damage from the sun is greatest from about 10 a.m. to 2 p.m. each day, so make sure you have your sunglasses handy.

Wondering if a single day of sun exposure can cause damage to your eyes? Dr. Swartz explains that several problems can develop from a single day in the sun if you don't protect your eyes, such as photokeratitis and eyelid sunburns. But "most problems develop from cumulative sun exposure and the damage will not appear until years later."

Prevention, Dr. Blecher stresses, is key.

If you wear contact lenses and have a UV-protected pair, they do protect the front surface of the eye. But Dr. Blecher wants you to keep in mind that "it doesn't protect the eyelids and other delicate tissues of the eye" like sunglasses do.

Another way to protect your eyes

After you've invested in a good pair of sunglasses, you may also want to consider buying a hat with a brim of 4 inches or more to shade your face from the sun. Wearing a wide-brimmed hat on sunny days will reduce your eyes' exposure to radiation by 50 percent, says Dr. Swartz.

So the next time you're out enjoying the hot summer sun, sport those shades and hats – and don't forget the sunscreen.

If you have questions or would like to schedule an appointment with one of our ophthalmologists, please call 1-800-JEFF-NOW or use our Find A Doctor online tool.

Rated third in the nation for Ophthalmology by U.S.News and World Report and recognized as among the best by Philadelphia magazine, Wills Eye Institute provides general eye care and nine subspecialty services attracting patients from throughout the Delaware Valley, across the country and around the world.