Q. What type of sunglasses should be used to provide the best UV protection? Is there a way to know if I am buying protective sunglasses?
A. UV light can cause damage to the conjunctiva and cornea, promote cataract formation, and can accelerate macular degeneration. Wearing the appropriate kind of sunglasses can help prevent or slow these types of problems. The American Optometric Association states that lenses should block 99 percent or more of both UVA and UVB light for maximum protection. Labeling of sunglasses for the amount of UV blocked is voluntary and not all lenses are made the same. In many cases, cheaper lenses block less than this recommended percentage. Manufacturers that are serious about providing lenses that offer the best protection for your eyes will often state that their lenses block 100 percent of UV light under 400 nanometers.
Rob McGarvey, O.D.
Kapperman and White EYECARE
1720 Gunbarrel Road, Suite 100
Chattanooga, TN 37421