Choosing sunglasses: Is UV protection important?

I was shopping for sunglasses recently, and I noticed that some say "100 percent UV protection" and others don't. Is UV protection important for sunglasses?

- No name / No state given

Answer

Yes. Ultraviolet (UV) radiation from the sun can damage your eyes as well as your skin. Strong sunlight can burn the corneas and conjunctivas of your eyes. In addition, long-term exposure to UV radiation can contribute to eye disease, especially cataracts. So, choosing sunglasses that provide UV protection is very important.

In the United States, the government has recommended that all sunglasses — prescription and over-the-counter — block ultraviolet radiation. Ideally, sunglasses should block the two components of UV radiation — UVB and UVA — by 99 percent and 95 percent, respectively. This is in accordance with the American National Standards Institute, a nongovernmental body that has set standards for sunglasses and fashion eyewear. If no claim of UV protection is made, it is impossible to know how much UV protection is present. Remember, untreated plastic lenses do not adequately block UV radiation.

When choosing sunglasses, you have a wide array of options. Here are some tips on what to look for:

• Blue-blocking plastic lenses. Often promoted for sun protection, blue-blocking lenses also block red, amber and blue light — which makes it difficult to discriminate traffic light colors. Blue-blocking lenses fail the guidelines established by the American National Standards Institute.
• Polarized lenses. Although polarized lenses protect against glare, they don't meet the criteria for UV protection unless they have additional UV-blocking material in the lenses.
• Photochromic lenses. This type of lens protects the eyes from glare, sun and UV radiation while also maintaining visual acuity. Also, photochromic lenses do not distort color.
• Polycarbonate lenses. A wise choice for children and athletes, polycarbonate lenses shield the eyes from UV radiation as well as protect the eyes against impact injuries that may be sustained during play and sports.

Standard glasses can also be treated with a material that absorbs UV radiation sufficiently to protect the eye while retaining a clear, nontinted appearance. In addition, UV protection can be obtained for most rigid contact lenses and many soft contact lenses.

Additional tips for protecting your eyes in the sun include:

• Choose sunglasses that fit close to your face or have wraparound frames.
• Wear a wide-brimmed hat or cap, which keeps out sunlight from directly overhead.
• Never look directly at the sun — even through sunglasses — because doing so can cause permanent eye damage.

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