Health & Fitness: Do Your Shades Do the Job?

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What is the de rigueur fashion accessory intended for outdoor use but often worn indoors, made famous by celebrities seeking anonymity but now flaunted by just about everyone? Sunglasses, of course. Last year Americans snapped up 189 million pairs (sales: $1.3 billion), from retro-1950s plastic shades to space- age wire rims with mirrored lenses. When it comes to protecting the eyes, however, the emphasis on style may be shortsighted. A cheap $5 pair of sunglasses picked up at a beachside stall may do a better job than those $200 movie-star specials. What's more, the quality of your glasses matters. Says Ophthalmologist Hugh Taylor of Johns Hopkins University: "People should be able to buy the sunglass equivalent of No. 15 sun block."

That is now difficult to do, and the consequence may be costly: prolonged exposure to invisible ultraviolet beams of sunlight may permanently damage the eyes. Ultraviolet-B is thought, for example, to be a major factor in the formation of cataracts, in which the normally transparent lens of the eye becomes cloudy or opaque. About 15% of people over 65 suffer reduced vision from cataracts; many eventually undergo surgery to have the lens replaced. Some ophthalmologists also believe that decades of absorbing ultraviolet-A may lead to destruction of cells in the center of the retina. The condition, known as macular degeneration, is a leading cause of blindness in the elderly. Unlike cataracts, it is not correctable. While acknowledging that the evidence linking sunlight to cataracts and retinal damage is not conclusive, many doctors now recommend that adults, and children too, use sunglasses that absorb nearly 100% of the ultraviolet rays.

Regular tinted sunglasses that protect the eye from visible light do not < necessarily screen out harmful rays. To stop UV light, lenses must be treated with a special pigment that absorbs the damaging rays. Eye specialists caution that untreated sunglasses may be worse than no sunglasses at all. Reason: without dark glasses, people squint and blink in the sun, minimizing the amount of UV light reaching the eye.

How are consumers supposed to tell good glasses from bad? It is not easy. Last year manufacturers adopted a voluntary labeling code developed by the nonprofit American National Standards Institute. Some glasses now carry tags saying MEETS ANSI STANDARDS. But critics charge the labels are inadequate. ANSI divides sunglasses into three categories: fashion spectacles that shield eyes from only 70% of UV-B and less than 60% of UV-A; everyday eyewear that screens out 95% of UV-B and between 60% and 92% of UV-A; and special-purpose glasses that absorb almost 99% of ultraviolet rays.

The information, however, is not included on all the tags. Says a spokesman for the Food and Drug Administration: "If you're a consumer and there's a rack of sunglasses, you usually have no way of telling the amount of ultraviolet transmission." The agency is now considering proposals to establish mandatory labeling standards for the sunglass industry. Ultimately, say experts, the best solution may be a simple rating system similar to the numerical system now used with sunscreens.