How should we be protecting our eyes from the harmful effects of the sun? What are the fine points involved in choosing sunglasses? We picked up some pointers on these questions from Dr. Haşim Uslu, an expert in eye health from Fatih University.
Summer is rolling around again, and though the sun and its rays have not made themselves too hot yet, they are definitely being felt more than a few months ago. No question that it is our eyes that feel the effect of these seasonal changes the most. Those with sensitive or damaged eyes can have a particularly difficult time during these months. Those that have a difficult time seeing in front of them on the sidewalk due to the strong rays of the sun have an even more difficult time driving cars — here’s where sunglasses come to the rescue. Though sunglasses may appear to be a simple solution, the truth is that finding and using the right pair of sunglasses involves details that we must not neglect.
Global warming also an enemy of the eyes
Human eyes see rays sent out by the sun that are between 400 and 780 nanometers (nm). When these rays decrease in size, they appear more blue-like, and when they grow, more reddish. Though UV (ultraviolet) rays make up only 5-6 percent of the sun’s rays in total, they are very dangerous. With the natural system damaged through the harm to the ozone layer caused by global warming, there is more and more of a risk presented by these UV rays, especially during the summer, when the general risk is 2-3 times as much as during the winter. Just as these harmful rays come directly from the atmosphere, shiny surfaces around us (like water, sand, grass, snow and so on) can reflect these rays back onto us and our bodies. And in the end, the eyes receive damage. The solution is of course sunglasses, made with special colored lenses, meant to protect our eyes from harmful rays and too much sunlight.
What sort of damage occurs in the eye itself?
In people who have been over-exposed to the rays of the sun, abrasion of the cornea and conjunctiva can be seen. There can also be pterygium, which is a benign growth of the conjunctiva. UV rays can also ruin the proteins inside the lenses, leading to the formation of cataracts. Though the cornea and lens of the eye absorb most of the harmful UV rays, just a small amount of UV rays reaching the retina can cause problems on the nerve layer of the retina.
Pay attention when buying sunglasses!
Using a good pair of sunglasses is the most effective way of protecting your eyes from the harmful rays of the sun, which is why real sunglasses are less of a clothing accessory and more of a necessary tool for health and protection. Perhaps the most important factor in choosing sunglasses is making sure the sunglasses sit perfectly on your face, or that they are right for your particular facial anatomy. Choose sunglasses which do not apply unnecessary pressure to your ears and your nose; try to make sure the glasses cover a larger surface on your face in general. Lean towards larger pairs of sunglasses, which will prevent harmful rays from reaching your eyes from the top, the sides, or underneath the glasses.
Not every pair of sunglasses is really able to hold back ultraviolet rays. And the idea that somehow dark-colored lenses prevent ultraviolet rays from coming through is not right. In fact, normal, uncolored lenses can prevent UV rays too.
Sunglasses need to be in keeping with certain necessary standards and most possess a certificate of quality. You should definitely check to make sure that the lenses on your glasses offer 99 percent UV ray protection, and that they filter rays under 400 nm.
Expensive sunglasses are not always the best choice. The optical quality of the lenses on your sunglasses needs to be quality, and there should be no scratches on the lenses when you buy them.
There is one practical way to understand whether the lenses of your sunglasses are quality; hold the glasses up to a vertical line — this could be a window or a doorframe — and then move the glasses lightly up and down, or from right to left. If the line warps or bubbles at all, the lenses are not quality, and you should forget about buying the pair. One other note: There is no age limit for the benefits of wearing sunglasses. Adults and children alike should use good sunglasses whenever they are exposed to the rays of the sun for a long time.
If you already wear glasses due to poor eyesight, but you also want to protect your eyes from the rays of the sun, one route you could take is to have a colorless UV-protective covering put on top of your normal lenses.
Brown and grayish lenses are the easiest for people to wear, and take the least time to get accustomed to for sunglasses wearers. Be warned that brightly colored lenses can also cause seeing problems when it comes to traffic lights, though this factor does not necessarily have anything to do with protection from UV rays. Also note that on quality lenses, there should be no bumps or bubbles. And when you press these lenses with your fingers, the glass of the lens should not move or stretch.