Athletics: Sunglasses - Not Just A Fashion Statement

By JAMES RAIA

Whether you're a long-distance runner, mountain biker, traveling salesperson or a bird watcher, the most important reason to wear sunglasses is to protect your eyes against ultraviolet radiation.

Unfortunately, while trying to emulate movie stars and fashion models, consumers often pay top dollar for trendy sunglasses advertised with fancy slogans but offering insufficient protection.

The American Optometric Association (AOA), estimates more than $2.5 billion is spent annually nationwide to purchased approximately 275 million pairs of sunglasses.

While such companies as Bausch & Lomb, the world's largest sunglass manufacturer, Vuarnet and Oakley have well-established market niches, numerous others including Killy, Hobie, Serengeti, Gargoyles, Revo, Rudy Project, Nikon and Swiss Army all tout their brands with varying marketing savvy.

But the perceived mystique, glamour and "coolness" of wearing sunglasses should never be overshadowed by the more important issue of eye protection.

"There's a lot of hype in the sunglass market," said Dr. Donald G. Pitts, a former U.S. Air Force optometrist and a professor of environmental vision and anatomy at the University of Houston College of Optometry. "The fancy words and slogans mean nothing, except the sunglasses usually cost more.''

Without such protection, exposure to ultraviolet (UV) radiation, particularly abundant in natural sunlight reflected off snow or sand and at high altitudes, can cause keratoconjunctivitis, a temporary inflammation of the eyelid lining or the cornea. Snow skiers call the condition "snow blindness.''

More devastating, UV radiation can also permanently damage the retina, the vision mechanism inside the eye. Ultraviolet radiation is also a leading contributor to cataracts, the clouding of an eye lens that obstructs the passage of light.

"I don't think people have to be paranoid and protect their eyes indoors and every time they step out their door," said Dr. Anthony Cullen, director of the school of Optometry at the University of Waterloo in Canada. "But if it's bright outside, if there's either reflected or direct sunlight, they should wear protective sunglasses. It's best to err on the side of caution."

As one of the three components of solar energy, invisible ultraviolet radiation has three levels, defined as UV-A, UV-B and UV-C. Range of ultraviolet light is determined by nanometers, the international wave-length measurement. One nanometer equals one billionth of a meter. Ultraviolet-C is solar energy measured below 286 nanometers. Ultraviolet-B is defined as 286 to 320 nanometers, and UV-A is 320 to 400 nanometers.

Although it may change as the ozone layer further erodes, UV-C radiation is believed to be effectively absorbed by the ozone, the earth's upper oxygen atmosphere. Ultraviolet-B is the solar energy that causes sunburn.

Although the potential dangers of UV-A are not as well documented, experts believe sunglasses should protect against at least 98 percent of UV-A and UV-B radiation.

In addition to percentage of UV protection, consumers should also consider optical quality, frame construction, proper color vision characteristics and other options such as polarization and mirror coating.

In the sports sunglass market, the largest share of the industry, Polycarbonate lens, which are nearly shatterproof, have become an industry standard, replacing glass and plastic.

Mirrored sunglasses have the same properties of a two-way mirror, provide maximum infrared light protection and are designed for wear in glare from snow or water. Polarized glasses eliminate glare and are universally recommended by eyecare specialists.

"You can find a pair of sunglasses on the rack that costs $25 or $30 and meets the UV protection and construction standards and you can buy a pair for $150 that's locked behind some case that doesn't meet any standards," said Dr. Pitts. "Price just isn't a good way determine the quality of sunglasses."

© Copyright 2004, James Raia

Posted with the permission of James Raia.

Subscribe to James Raia's Endurance Sports News and Tour de France Times at: www.byjamesraia.com. They're free and spam-free.