Sunglasses are not just a stylish fashion accessory. They are quite literally a front-line protection for your eyes.
UV (Ultraviolet) radiation is a component of light that does not fall within the visible spectrum of light. Thus, even on cloudy days when there is little perceptible sunlight, your eyes can be exposed to UV rays.
There are three categories of UV radiation, which each have different levels of risk to you.
While UVC rays have the highest energy of the UV radiation varieties, and are theoretically the most dangerous for your eyes, the planet’s natural ozone layer in the atmosphere blocks almost all UVC rays and prevents them from reaching us.
UVB rays, however, are only partially filtered out by the ozone layer, with a portion making its way to us on the surface. Low doses of UVB rays are responsible for suntans, though overexposure can lead to the far less desirable sunburn, in addition to raising the risk of skin cancer. Too much UVB exposure can also lead to premature aging of the skin in the form of discolorations and wrinkles.
They can lead to eye problems as well. Too much UVB exposure can lead to photokeratitis, pinguecula , and pterygium.
UVA rays, which are lower energy than UVB and UVC, and which are closest to visible light, are particularly dangerous because they can pass through the cornea and into the retina of the eye.
Too much UVA radiation exposure can lead to the development of several types of cataracts, and may be linked to macular degeneration as well.
The UV index created by the National Environmental Protection Agency and the National Weather Service gives you a color-coded warning system to keep people aware of the level of UV risk on any given day.
Sunglasses are the single best way to protect your eyes from UV radiation. However, not all sunglasses are equal. You should be wearing sunglasses that are rated to block 100 percent of UV rays while outdoors during daylight, even on cloudy days. While clouds obscure visible light, the more damaging UV rays are not so easily stopped. It is also recommended that you wear sunglasses with close-fitting frames, as they provide additional protection on the sides of your eyes.
It should also be noted that the color or darkness of the lens does not mean it is any better or worse at protecting you from UV rays. Your optician will be able to verify the level of protection your lenses will provide.
Larger lenses can also provide protection not only for your eyes, but for the delicate skin around them.
In addition to sunglasses, wearing a wide-brimmed hat on sunny days can reduce UV exposure to your eyes by up to 50 percent.
Damage to the eyes and skin from UV radiation is cumulative, so it is highly recommended to start protecting your eyes from an early age. Especially since children tend to spend more time outside than adults, so much so that some experts say that more than half of a person’s lifetime UV radiation exposure can occur by age 18, they should be wearing sunglasses while outdoors.
Additionally, since the lenses inside childrens’ eyes are usually clearer than those in adults, it is easier for UV rays to penetrate deeper into the eye.
While the price of sunglasses doesn’t necessarily determine how well they’ll protect your eyes, it is probably best to avoid the cheapest options you’ll find in supermarkets or drugstores.
Tinted lenses may cut down on the glare from sunlight, but if they don’t include proper UV blocking, they can actually lead to more eye damage as the eyes, thinking it’s darker around them, will dilate the pupils and let in more UV rays.
When shopping for sunglasses, look for ones with a sticker or tag that indicates how well they are able to block UV rays, and purchase only ones that provide 99 or 100 percent protection. Additionally, it is recommended to look for sunglasses which include an antireflective treatment to the back side of the lenses, as a significant amount of UV rays that reach the eyes are reflected from the back surfaces of lenses.
When choosing sunglasses, go for those that will fit your face well and provide protection, over something stylish.