Sunglasses – More Than Just Fashion
The sun produces many different kinds of energy. The energies most likely to injure the eye are invisible ultraviolet radiation (often called UV rays), bright or intense light and blue light that comes from the reflection off water or snow.
Ultraviolet radiation (UVA & UVB) carry more energy than visible light rays, so the eye is at greater risk of damage from absorbing UV rays than from absorbing other kinds of light. UVA and UVB rays can cause, or speed up the progress of, several diseases that affect the eye. UVB rays have also been linked to skin cancer. Most of the damage caused to eyes by UVB and UVA rays happens over a long period of time and cannot be reversed.
If eyes are overexposed to UV radiation, the front portion of the eyes can be damaged. If visible light is too bright or intense, or if you stare directly at the sun, even briefly, the retina can be damaged, causing permanent loss of vision. UV radiation, along with wind and drying of the eye, may cause snow blindness, an uncomfortable but temporary condition. There is some evidence that daily exposure to UV radiation in very bright sunlight over many years may increase the risk of developing cataracts. Cataracts cause a gradual clouding of the natural lens of the eye.
Tips for choosing sunglasses
Sunglasses are an important tool for protecting your eyes from sun damage. Here are some guidelines to choosing the right pair:
- The colour and darkness sunglass lenses have nothing to do with the sunglasses’ ability to block UV rays. Choose sunglasses that block 99 to 100 percent of both UVA and UVB rays. Avoid sunglasses that neglect to offer details about their UV protection.
- If you spend a lot of time outdoors with intense glare from sunlight bouncing off water ( or snow), you should wear sunglasses that block blue light. Medium to dark lenses with a grey, or slightly brown or green tint, will filter out most blue light. Blue-blocking lenses can make distant objects easier to see, and are popular with skiers, boaters and hunters. Lenses that block all blue light are tinted amber. However, when driving, it’s recommended that tinted sunglasses be gray to ensure proper traffic light recognition.
- Polarized lenses reduce reflected glare, such as sunlight that bounces off snow or water. They’re useful for skiing, driving and fishing.
- Polycarbonate lenses should be considered for sports since they offer impact protection during potentially hazardous activities.
- Follow these guidelines to reduce your risk, but go ahead and choose stylish lenses to release your inner Risky Business!