Seems like an elementary question, no? Cut out a couple of pieces of glass, tint them, slap them inside a set of cool frames, and presto! You have sunglasses! They’re pretty much all the same, right?
Actually, you may have already guessed that not all sunglasses are created equal. If you are in the market for a good pair of shades, it might help to remember the adage “Never judge a book by its cover.” The same can be said for sunglasses: they may look trendy, but won’t necessarily keep your eyes healthy. To know what to look for, it helps to understand how they work.
The tinting on sunglasses may serve one or more purposes. The main function of sunglasses is to reduce the amount of visible light that enters the eye. The part of the eye known as the iris responds to visible light by getting smaller, effectively reducing the amount of light that reaches the retina. This is a purely physiological response which protects the eye from the damage that too much sunlight can cause.
Sunglasses, depending on how they are manufactured, can also protect the eye from ultra-violet (UV) rays from the sun. It has long been known that UV rays are directly responsible for skin cancer, as well as blindness, cancer, and other degenerative diseases of the eye. Some UV protective glasses are specialized even further to block very specific frequencies of light, which may be especially helpful to people who are exposed to sunlight for long periods during the day due to the type of work they do, such as lifeguards, construction workers, gardeners, etc.
So why won’t any old pair of shades do? It may surprise you to learn that you’d actually be better off wearing no sunglasses at all than to use a pair of cheap ones. Cheap glasses are manufactured with only a thin coat of tinting, and typically do not block UV rays. By wearing this type, you are forcing your iris to remain open wide (instead of getting smaller as it would when sunlight enters it directly), which in turn allows even more dangerous UV light to enter than would if you wore no sunglasses at all. In short, you may look hip and trendy, but in the long run you are risking your eyesight. This is not to say that you should simply avoid wearing them at all. On the contrary, medical professionals and scientists recommend that EVERY person, regardless of age or profession, wear UV protective eyewear EVERY time they go outside. Just make sure it’s the RIGHT pair.
With this information in mind, here are a few tips to help you choose a pair of UV lenses that not only look dashing, but protect your eyes as well:
o Darker tints are generally better. Look for the darkest tint you can find without restricting your visually acuity.
o Consider when and where you will most often wear your sunglasses. The color of the tint has different effects on the amount and type of light that enters your eye. This will have a bearing on the color of the tint that you’ll want to choose (black, brown, pink, etc.).
o Pay attention to the UV rating. Remember, not all sunglasses block UV rays, so look for ones that are labeled “UV protective” or have a UV rating of 400 or more, which means that they will block at least 98% of UV rays. Anything less may do more harm than good.
o Think about whether you plan to spend a lot of time outside in the snow or around water. Sunlight that is reflected off of bright surfaces such as snow or water becomes “polarized”. Look for glasses labeled “polarized,” which will reduce the glare from reflected light, something non-polarized lenses will not do an adequate job of.
o Frame size matters too. If the frames are too small, too much light will enter into your eyes through the sides of the sunglasses, greatly reducing their effectiveness. Choosing larger frames keeps more light out, and also protects the vulnerable, thin skin around the eyes too.
If you’re worried about sacrificing fashion for health, you needn’t. There are hundreds of sunglasses manufacturers with thousands of the most current styles in stock, for every age from babies to adults. So you can rest assured knowing that you’ll not only preserve your health and sight, you and your family will look great too!