Darker sunglasses can be worse for the eyes

Darker sunglasses can be worse for the eyes, ophthalmologists say. In interviews with MedPage Today, experts explained how heavily tinted sunglasses can actually allow more ultraviolet light to penetrate the eyes and cause damage. Normally, the pupils constrict in high-light conditions for protection, but sunglasses can inhibit this natural physiological response by dimming the incoming light. “Dark shades cause more harm because you lose that protective reaction: you don't squint, your pupils don't constrict," Dr. Kondrot of Fla. stated. “And you get excessive amounts of sunlight into the eyes.”’ Rather than searching for heavily tinted sunglasses, experts argue that finding a pair that absorbs ultraviolet rays is most important. UV rays are outside the visible light spectrum, with higher energy that can alter chemical bonds upon reaching the earth’s surface. The typical manifestation of overexposure to UV light is sunburn, but these rays can also be very harmful to the eye, leading to photokeratitis, retinal damage, or possibly cataracts. Additionally, while polarized lenses are helpful in reducing glare, they do not prevent UV light penetration. Only sunglasses with high UV light absorption can protect the eyes sufficiently from the dangers posed by heavy sunlight.