Sunglasses

Why wear sunglasses?

Rays from the sun, called ultraviolet light, can damage the eyes. Wearing the right kind of sunglasses outdoors may reduce the risk of eye damage from ultraviolet light.

What eye problems are related to exposure to sunlight?

Ultraviolet (UV) light from the sun may help cause:

• cataracts. A cataract is a cloudy area in the lens of the eye. The lens is located inside the eye behind the iris (the colored part of the eye). The lens gets cloudier over time and causes vision problems. Vision can then be restored only with surgery.
• age-related macular degeneration (AMD). AAMD is a disease that damages the macula in the eye. The macula is in the center of the retina. The retina is the lining at the back of the eye that senses light coming into the eye. The macula allows you to see fine details in the center of your field of vision. AMD can make it hard to read, drive, or recognize faces.
• pterygium or pingueculum. These growths on the outer coat of the eye that are common in people who spend a lot of time outdoors in sunny climates.
• skin cancer. The eyelids are a common place for skin cancers.
• sunburn of the cornea (the clear outer layer on the front of the eye). This may also be called snow blindness.

What kinds of sunglasses reduce eye damage from sunlight?

Most modern sunglasses provide good protection against UV. The more ultraviolet rays are blocked, the more the eyes are protected.

Polarized lenses reduce glare reflected from surfaces such as water or snow. However, they don't block UV light unless they are combined with a coating that blocks UV. Mirror coatings alone do not provide UV protection and should be combined with a UV-blocking coating.

Photochromic lenses are almost clear in low light and turn darkly tinted in bright light. They react to UV light and not to visible light. A car windshield blocks out most UV light, which means that photochromic lenses will not darken in the car. Ask your eye care provider about tint options.

Who should wear sunglasses?

Wide-brimmed hats may keep about 50% of UV rays from reaching the eyes, but your child should also wear sunglasses. Sunglasses are very important if your child:

• already has eye problems
• takes certain medicines, such as tetracycline, allopurinol, phenothiazine, and psoralen
• is outdoors at high altitude or near the equator
• spends a lot of time on snow or water