As with skin, ultraviolet rays penetrate the eyes at different depths, causing lasting damage. With short exposure to the sun, the rays typically don't cause much harm, as the human eye can filter them out. However, prolonged exposure to UV radiation can cause serious eye illnesses, such as photokeratitis (inflammation of the cornea), pterygium (the formation of a spot on the eye's surface), and even cataracts, the leading cause of blindness in the world.
According to an estimate by the World Health Organization, 20 percent of cataract cases are related to excess UV radiation. Fortunately, reducing your odds of developing these eye conditions is as easy as wearing a pair of sunglasses when exposed to sunlight.
The Science of Sunglasses
In addition to elevating your style, wearing sunglasses has several benefits to your vision. While filtering UV light, they reduce glare during the day or when exposed to bright lights, preventing you from having to squint to see. They also protect your eyes from elements such as dust, sand, and wind, which can injure the cornea.
When shopping for sunglasses, you'll likely come across inexpensive models that do very little to protect your eyes. To avoid spending on a purely ornamental pair of sunglasses, be sure to read the label or online product description and check for the product's UV protection specs. Ideally, you want a pair that blocks 99 to 100 percent of UVA and UVB rays. You can look for sunglasses with a UV-400 label, meaning they can absorb 400 nanometers of UV light.
When to Wear
According to a 2019 article by Time magazine, some moments of the day and specific environments are more hazardous to your eyes than others. It's important to note that reflected sun, not just direct sunlight, can damage your eyes. That means you can take in up to twice as much UV radiation if exposed to both direct sunlight and the reflected light, for example, when boating on open water on a sunny day. Ideally, you should wear sunglasses under all the following circumstances:
- In the Afternoon Sun– In addition to protecting your eyes from UV radiation, sunglasses help you see better in the afternoon sun by reducing glare and improving colors and contrast.
- While Driving– Driving on sunny days can be challenging, as sunlight reflects off the hood of cars and other objects. Sometimes, the reflected light can even blind you momentarily and cause an accident. Wearing sunglasses can allow you to see better while driving, even during cloudy conditions.
- While Playing Outdoor Sports and Other Outdoor Activities– In addition to blocking UV rays, sunglass lenses work as a shield against sand and dust carried by the wind, which can scratch your cornea and cause permanent damage.
- At the Beach or by the Pool– Both sand and water can reflect sunlight. Sunglasses can reduce glare for those who spend a lot of time in the water or on a boat. Choose models that fully cover your eyes, including the sides.
- On Bright, Snowy Days– Snow reflects 80 percent of the sun's UV rays. There's a condition known as snow blindness, where excessive brightness burns the cornea. Even on chilly winter days, you should wear sunglasses that cover the lower part of the eyes.
While wearing any UV-protective sunglasses is better than nothing, certain sunglass models work best for different conditions and activities. When looking for a new pair of sunglasses, consider the following elements carefully:
- Prescription Sunglasses and Clip-on Sunglasses– Prescription sunglasses work exactly like prescription glasses while protecting your eyes from UV rays. However, it can be costly to buy high-quality pairs of regular prescription glasses and prescription sunglasses. If you're looking to save on your eyewear needs, consider an eyeglass and sunglass clip-on set. With your prescription glasses, you'll get non-prescription sunglass lenses on a specially-fitted frame that clips directly on to your regular glasses. You can click here to browse clip on sunglasses online.
- Polarized Lenses– Polarized sunglasses reduce the glare of sunlight reflected off different surfaces, helping filter and block excess light.
- Photochromic– These lenses automatically darken when exposed to strong lights and lighten in low-light environments.
- Tints– According to optometrists, the color of the lens does not mean greater UV protection. Lens color, however, can improve your vision in other ways. For example, red lenses can block the blue light emitted by a computer screen, while green lenses improve contrast and sharpness, and yellow or orange lenses are more practical to wear when driving during fog.
The Right Sunglasses for Your Lifestyle
Wearing sunglasses is just as critical to your health as wearing sunscreen, so you'll want to ensure you have the best product for your lifestyle and unique eye health needs. When buying a new pair, talk to your optometrist about what features you need in a new pair. Ideally, your new sunglasses should help you drive safely, see better on very bright days, and even use your computer with less strain on your eyes.