You know that when you go to the beach you have to put on sunscreen and put up the umbrella. But did you know that you also need to protect your eyes, even when you are wearing a hat or sitting under an umbrella? You need to wear a pair of sunglasses that block harmful ultraviolet (UV) light. The super cheap kind won't do.

UV damage is just as bad for your eyes as it is for the rest of you. It can cause cataracts, corneal degeneration and other serious eye problems, according to the American Optometric Association (AOA).

These conditions have effects ranging from blurred vision, irritation, redness and tearing to temporary vision loss and even blindness.

"Just as skin is 'burned' by UV radiation, the eye can also suffer damage. The lesson — especially for young people — is that eyes need protection, too. Protection can be achieved by simple and inexpensive methods such as wearing a brimmed hat and using eyewear that properly absorbs UV radiation," says the AOA's Gregory Good.

Children and teens need to be particularly careful about sun-related eye damage, because the lenses of their eyes are more transparent and let in more UV light than those of adults.

It is a message that few Americans seem to have heard. A 2007 survey found that 40 percent of Americans did not realize that UV protection is an important factor to consider when buying sunglasses. The same survey also found that 23 percent of Americans fail to check if the lenses they buy for their kids provide UV protection.

How can we protect our own eyes and those of our children? The AOA offers the following advice:
  • Wear protective eyewear any time your eyes are exposed to UV radiation, even on cloudy days and during the winter.
  • Purchase sunglasses that offer good UV protection.
  • Make sure sunglass lenses are free of distortions or imperfections.
  • Buy gray-colored lenses. They reduce light-intensity without altering the color of objects.
  • Make sure children and teens wear sunglasses whenever they are outdoors.