Ultraviolet (UV) light can damage your eyes. Wearing the right kind of sunglasses outdoors may reduce your risk of eye damage from ultraviolet light. UV rays are as strong on cloudy days as on sunny days.
UV light from the sun increases your risk for:
UV protection is not related to how dark the lens is. Look for sunglasses that protect you from 100% of both UVA and UVB light. This includes those labeled as "UV 400". If the label says only "blocks most UV rays", the glasses will not protect your eyes.
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 dark 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.
Lens color does not affect how well sunglasses protect your eyes. Gray and brown are least likely to distort the colors you see. Skiers may choose yellow lenses to help reduce haze in low light.
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: