It is widely known that excessive UV-A and UV-B rays cause sunburn and skin cancer, but fewer people realize they also cause sunburned eyes. Growing scientific research has led leading authorities such as the American Academy of Ophthalmology to warn that repeated exposure to ultraviolet (UV) radiation and near-UV light can contribute to cataracts and macular degeneration. The lens of the adult human eye will absorb a certain amount of UV radiation and near-UV light to protect the eye. However, long hours in the sun or exposure to severe glare overwhelms our natural defenses, causing sunburned eyes that result in a painful condition called photokeratitis or snow blindness. This condition usually heals on its own in about a week, but repeated bouts can lead to scar tissue and eventually contribute to cataracts.

We can see and feel our skin becoming sunburned, but we can’t feel our eyes getting sunburned. Lightly sunburned eyes cause symptoms a few hours later. Dryness, itchiness, burning, tearing, and heightened sensitivity to light are all typical. Most often, the cause is not attributed to sunburned eyes, and often the eyes are repeatedly sunburned, especially during summer and winter months when UV radiation is intensified, reflecting off snow and water. Over the years, repeatedly burning the eyes can lead to serious and permanent vision impairment.

Though doctors have long known about UV dangers, studies now suggest that toxic exposure to near-UV light, known as high-energy visible (HEV) or blue light is a possible contributor to macular degeneration. This chronic disease of the retina is one of the leading causes of blindness, with early symptoms including loss of detail in the central vision. Tasks like reading and driving become problematic as the disease worsens.

To protect your eyes from harmful rays, routinely wear sunglasses whenever outdoors. When shopping for sunglasses, note that darkness of a lens isn’t an indicator of how well the sunglasses protect. Dark lenses cause the irises to open wider, letting in more light. If the lenses do not have a high degree of UV and HEV protection, the eyes will become more sunburned.

Look for the words 100% UVA and UVB protection and HEV, near-UV or blue-light filtering. The less-harmful HEV rays needn’t be filtered out completely. Yellow lenses block all HEV light, removing blue and distorting true color. Amber and melanin lenses filter HEV light while retaining more true color.

Children’s eyes should also be protected. Shade or an umbrella will not prevent a child from getting sunburned eyes on a beach, by a pool, or in other highly reflective environments. For maximum protection, choose frame styles that do not allow excessive light to enter at the top or sides.