Most Americans are familiar with the hazards of Ultraviolet (UV) rays to your skin, (particularly sunburn and skin cancer) and the need for applying sunblock and using other forms of sun protection when spending time in the sun. What is less known is that ultraviolet rays and other types of radiation from the sun also pose a danger to your eyes.

If you often go out without proper eye protection, think about this: Extended contact with the sun's UV light has been seen to be a cause of damage to the eye.

UV Risks to Vision

Excessive short term exposure to UV is known to cause photokeratitis or a ''sunburn on the eye'', leading to pain, blurred vision or even temporary blindness. In the long run, UV exposure can cause more threatening eye diseases such as cataracts, macular degeneration, and others, which can cause loss of sight. Just like the real thing, tanning beds pose a substantial risk of overexposure to UV.

UV Eye Protection

For proper UV defense, sunglasses should keep out 100 percent of ultraviolet radiation. Look for shades labeled ''UV 400'', which indicates that they block all light rays with wavelengths up to 400 nanometers (which includes both UVA and UVB rays, both known to enter the atmosphere).

You also want to choose sunglasses with full eye coverage. Sunglasses with side protection can block harmful UV light from entering from the sides and back of the frame.

Those whose regular activity involves lengthy exposure to sunlight are at the highest risk for UV eye damage. Ultraviolet radiation can be bounced off of bright surfaces such as snow, water, and white sand and poses the greatest threat from 10 am to 3 pm and throughout the summer months. UV radiation levels increase nearer to the equator and at high altitudes. It's recommended that you consult with an optometrist and to know the risks for UV exposure. Simply putting on your sunglasses can be the key to protecting your precious eyesight.