Worth looking into: Contact lenses with UV filters provide complete protection.

RODALE NEWS, EMMAUS, PA—You've slathered yourself up with safe sunscreen, donned some UV-protective clothing, and are headed out to the beach. But if you've left your sunglasses at home, you're putting your precious eyes at risk for long-term UV damage that could lead to cataracts, cornea burns, and other eye damage or diseases. Even if you do grab your sunglasses, they may not adequately screen out both UVA and UVB rays. "During the summer, when more time is spent out in the sun, people start thinking about UV protection for their skin, but don't take similar steps to safeguard their eyes," says Jan Bergmanson, DO, professor at the University of Houston College of Optometry and founding director of the Texas Eye Research and Technology Center.

And you may not notice the damage that's being done, he adds, because long-term damage can take years to show up. Severe short-term effects of sun damage can produce irritation, tearing up, sensitivity to bright lights, and a burning sensation. "A common complaint is that it feels like you have sand in your eyes," he says. These usually take a few hours to appear, "but if you get a good burn, you'll suffer for a couple of days." Chronically underprotected eyes can develop cataracts or a disease called pterygium, a condition that can cause vision problems or even blindness. Pterygium is common in middle-aged and older adults, he says; in the South, where people are closer to the equator and spend more time outdoors, it affects up to 10 percent of the population. And, he notes, UV radiation is its only known cause.

Before the long Fourth of July weekend hits, spend some time shopping for good-quality sunglasses, paying close attention to a few details:

• "Polarized" does not equal "UV protection." "The fact that a pair of sunglasses could be polarizing has nothing to do with UV absorption," he says; polarized sunglasses simply reduce glare, and unless they're treated with a UV-protective coating, don't protect against UV rays. Dr. Bergmanson says to look specifically for sunglasses that advertise themselves as having UV protection and particularly those advertised as meeting certain criteria set by the American National Standards Institute (ANSI). At the very minimum, ANSI requires that sunglasses block 95 percent of UVB rays and 70 percent of UVA rays, but you can get better protection from "class 1" ANSI-rated glasses, which block 99 percent of UVB rays and 95 percent of UVA rays. This rating should be advertised on a product label somewhere, but if you're in doubt, ask your optometrist, says Dr. Bergmanson. Optometrists have equipment that can detect the UV protection level of sunglasses and corrective eyeglasses that have been treated with a UV coating. If there's no product label, assume that there's no UV protection. While you're shopping, look for wraparound shades, he says, so you block UV rays that can enter from the sides of your glasses.