Will the UV filtering effect remain the same after the sunglasses have been used for a long time?
The study does not directly answer the question of whether UV protection has worsened. The only way to know for sure is to test your sunglasses.
Sunglasses with recommended protection will filter out all UV rays. Ultraviolet light can damage the surface tissues of the eye, the cornea and the lens. Over time, UV damage can increase the risk of cataracts, macular degeneration and other eye conditions. These conditions can reduce your vision.
A 2016 study from the University of Sao Paulo in Brazil took a look at the adequacy of sunglasses' UV protection to test. "It's different than testing to see if the UV protection in sunglasses is going to go away," said Jeff Pettey, M.D., an assistant professor of ophthalmology at Moran Central University in Utah and a spokesman for the American Academy of Ophthalmology.
The researchers found that the Brazilian manufacturer's tests may underestimate the amount of UV exposure that can be caused to the glasses over time. It's not clear what the findings mean for the U.S. sunglasses test. Brazil's UV radiation exposure rate is higher than that of the United States.
While the study raises more questions than answers, Dr. Pettey said consumers shouldn't panic or rush to switch their beloved hues. No one is currently suggesting sunglasses for retirement.
Uv blocking technology has improved in recent years. Most sunglasses today have UV protection that is embedded in the lens, rather than coated on it. If you are concerned about the age and safety of your sunglasses, you can test them at an optical shop equipped with an ultraviolet light meter.
If you're ready to buy a new pair of sunglasses, Dr. Pettey offers these tips for choosing the most protective sunglasses: Look for a label that says "100 percent UVA and UVB protection" or "100 percent UV 400 protection." Choose a larger frame that covers your eyes and surrounding skin. Frames that wrap around the sides of the face provide maximum protection.
