UV Protection Comes at Any Price
Although sunglass claims increase each year, their most important health feature--blockage of ultraviolet, or UV, rays--is as likely to be offered on $10 drugstore shades as on designer brands, according to the American Academy of Ophthalmology.
Exposure to UV radiation increases the risk of cataracts, a clouding of the eye’s natural lens. In 1988, doctors who studied 838 Chesapeake Bay watermen found those who wore no eye protection had three times as many cataracts as the others. UV exposure can also lead to macular degeneration, retina damage that is the major cause of blindness among Americans older than 55.
A chemical coating on the lens surface of UV-protected sunglasses screens out UV-A rays--which constitute more than 90% of ultraviolet radiation and are most intense in the early morning and afternoon--and UV-B rays, most pronounced at midday. Widely available spectrum scans--which measure the UV light passing through a lens--let consumers check for UV protection before buying.
Sunglass standards set by the American National Standards Institute, a nonprofit, nongovernmental organization, are voluntary. But Commerce Department regulations bar manufacturers from falsely labeling claims like UV protection.
Even contact lenses that claim to be UV-absorbing have not been proven to shield against sun-caused eye diseases, and the academy recommends that people who wear contacts use sunglasses as well. The American College of Preventive Medicine reports that UV light, most intense in summer, is increasing worldwide.
Other sunglass features that merit attention, according to eye experts, include:
* Optical clarity. Wearing lenses that are optically precise and distortion-free helps prevent eyestrain and fatigue. Test for distortion by turning your head while looking through the glasses at a pole or a tree; a pole that appears to waver indicates a minor distortion. The priciest lenses aren’t always the best here. A study in the Journal of the American Optometric Assn. found that Revo and Serengeti, the two most expensive of six designer sunglasses tested, had the poorest optical accuracy.
* Fit. Glasses should be close-fitting and large enough to cover your entire eye, including your eyelid. Wraparound lenses may offer added protection.
* Tint. Get whatever color pleases you. According to the academy, darker-tinted sunglasses don’t block more UV rays than lighter-colored lenses.
* Polarized lenses. Useful for driving, boating and fishing, these minimize the sun’s reflection or glare from smooth surfaces like pavement or water. Polarization, however, has nothing to do with UV protection.
* Infrared protection. While sunlight contains some infrared light, research has not linked it closely with eye disease.
* Blue-blocking. Scientists disagree on whether blue light poses a risk to the eye, but this is not a high-priority summer concern, since the greatest exposure to blue light comes from snow reflection.
* Mirror-coated. A thin metallic coating reduces the amount of light entering your eyes and may be handy to hide behind, but it doesn’t protect fully against UV rays.
Parental note: Infants and children are more vulnerable to UV damage than adults. Eye experts recommend keeping children out of the sun between 10 a.m. and 4 p.m., when UV rays are strongest. Since eye damage from the sun is cumulative, they also recommend wearing sunglasses year-round.
