It's safe to assume that almost everybody is exposed to UV rays on a regular basis. However, the dangers related to long-term exposure to these harmful rays aren't really considered, to a point where most people barely take enough action to guard their eyes, even when they're expecting on being exposed to the sun for many hours. Being exposed to too much UV is dangerous and irreversible, and may also cause a number of severe, sight-damaging diseases in older age. And so, continuing protection from UV rays is equally important for everybody.
UV radiation, originating mostly from the sun, is made up of 2 types of harmful rays: UV-A and UV-B. Even though only tiny amounts of UVA and UVB light hit the inner eye, the eye cells are incredibly receptive to the dangerous effects of their rays. Even in the short term, small amounts of exposure can easily lead to sunburn of the eye, also known as photokeratitis. When UVB rays are absorbed by the cornea, the outer cells are severely damaged, which can cause blurred vision, pain or in serious cases, temporary blindness. UVA rays can enter the eye more deeply, which harms to the retina. After several years, UV rays can cause significant and lasting damage to eye sight. Of the 20 million people who suffer from cataracts, about 20 percent are due to extended exposure to UV rays.
A really great way to shield your eyes from UV rays is by wearing good sunglasses. Check that your sunglasses or prescription glasses block 100% of both UVA and UVB rays. Wearing an insufficient pair of sunglasses can actually be more harmful than wearing no sun protection at all. Consider this: if your sunglasses offer no protection against UV, you're actually getting more UV rays. The inadequate sunglasses generally reduce the light, forcing your iris to open and let even more light in. And this means that more UV will reach the retina. Always check to make sure your sunglasses offer enough protection against UV.
Wearing a broad brimmed hat or baseball cap will also block up to half of UV rays. A brimmed hat or cap can also reduce UV rays hitting the eyes from above or around glasses.
Years of exposure to UV rays can also cause an abnormal tissue growth on the eye, known as pterygium. This is a narrow, wedge-shaped tissue growth with blood vessels that grow over the white part on the surface of the eye. In addition to being cosmetically unsightly, a pterygium can be uncomfortable, and can even affect the curve of the eyeball, causing astigmatism. If the pterygium begins to grow over the cornea, it can affect vision and may need to be surgically removed. Because pterygia are the result of long-term UV exposure, it's totally avoidable.
Talk to your eye care professional about the various UV protection options, including, but not limited to, adaptive lenses, polarized lenses and fixed tint sunglasses.