Protecting our eyes from the harsh rays of the sun is not only an essential aspect of maintaining clear vision but also crucial in safeguarding our overall eye health. The sun’s ultraviolet (UV) radiation can have harmful effects on the delicate structures of our eyes, potentially leading to eye conditions such as cataracts, macular degeneration, and even permanent damage to the retina. With the eyes being highly sensitive to UV exposure, it is vital to take proactive measures to shield them from the sun’s harmful rays. Whether it’s a sunny day or even on cloudy occasions, incorporating effective sun protection for our eyes is a simple yet indispensable step towards preserving our vision and enjoying a lifetime of healthy eyesight.
What Is Ultraviolet Light & What Does It Do To My Eyes?
When talking about ultraviolet light – or UV light – it’s helpful to think of light as a spectrum. UV light is part of that spectrum, but is invisible to the naked eye. Unless you work as a mechanic regularly using heavy duty welders that produce their own UV light or make frequent use of a tanning bed, most of the UV light you will ever be exposed to in your lifetime comes from the sun. Let’s get familiar with UV terms and how we can improve our sun protection.
UV-A and UV-B
You’ve likely heard the terms “UV-A” and “UV-B” before, so what’s the difference? These are sub-classifications of UV relating to how “long” or “short” the UV wavelength is, from the peak of one “crest” of the wave to the next. UV-A rays have the longest wavelengths of UV light and are not blocked or hindered by the natural shielding in our atmosphere. This is the type of UV that we are most exposed to, and can cause damage to our eyes and skin cells. UV-B rays have shorter wavelengths and can be mostly absorbed by our atmosphere, but in certain parts of the Earth or at certain times of the year the amount of UV-B that can come through is far greater. UV-B is also significantly damaging to our skin and eyes, directly leading to significant skin burns and the development of skin cancer.
“UV-C” also exists, but the wavelength is so short this type of UV light is completely absorbed by our natural atmosphere, and thus we are never exposed to the harmful effects of it outside of a few, rare specific instances.
What does UV light do to our eyes when exposed?
UV light passes through our eyes more easily than even visible light, and can hasten the aging of the cells in our eyes much like it can with skin. This can result in the lens inside of our eyes becoming opaque and turning into an early cataract which will impair vision over time and eventually require surgical removal. UV light can also cause the growth of fat and protein deposits on the surface of the eye called a pinguecula that can cause irritation and can affect the tear film covering the eye. UV light can also cause skin cancers – basal or squamous cell carcinomas – to develop on the eyelids, and early research suggests a link between UV light and age-related macular degeneration, though more study on this link is needed.
As you can see, it’s just as important to protect your eyes from the harmful effects of UV light from the sun as it is to protect your skin while outdoors with UV blocking sunscreen. But while you can’t apply sunscreen to your eyes, there are options in the form of eyewear designed with sun protection in mind. Today, we’ll explore three of these options.
Photochromic Lenses for Sun Protection
The first option for sun protection is arguably the simplest. Sidestepping the need for an extra frame for sun lenses, photochromic lenses combine regular glasses and sunglasses into one convenient pair.
Photochromic lenses use the UV light to their advantage. These lenses are fabricated with additional organic molecules embedded in the material (either plastic or polycarbonate) that are transparent under normal lighting conditions. Once in the presence of higher levels of UV light, such as the amount produced by the sun, the molecules undergo a temporary chemical shift and lose their transparency, in effect becoming “darker”. Because this change only happens when exposed to UV light, returning indoors where most of the light is artificial the molecules return to their transparent state and the lenses become clear again.
Why choose photochromic lenses?
Photochromic lenses are an excellent option for their convenience and cost effectiveness. They are available in the three standard sun colours of grey, brown and grey-green, and a few manufacturers have been able to formulate lenses that change to more fun and fashionable colours such as blue and amethyst. There are some that can transition with a mirror coating, and others that are able to incorporate a polarization filter to further help with bright light and glare.
Are there any drawbacks to photochromic lenses?
While these lenses are convenient for their ability to adapt under certain lighting conditions and offer both clear vision correction and sun protection in a single pair, there are some drawbacks. Because these lenses need to be physically exposed to UV light to activate the change, most photochromic lenses cannot change while inside of a vehicle, as windows and windshields are coated for UV protection as an industry standard. On days that are both bright and simultaneously overcast, the lenses will not get as dark as they would on a cloudless day. Photochromic lenses are also sensitive to sudden temperature changes and temperature extremes, and the transition from clear to dark and back again is lessened and slows down.
Despite these drawbacks, photochromic lenses are an excellent choice for those who don’t want to worry about carrying an extra pair to swap to while outdoors. But for those who do want the superior protection of actual sun lenses, there is an option that is still convenient and more light-weight than a second pair of sunglasses.
Custom Clip-Ons for Sun Protection
Another option for sun protection can be just as simple as the previous: having clip-ons made to fit your primary pair of everyday glasses.
Clip-ons can be thought of as a separate pair of sunglasses, with many of the same benefits and avoiding the drawback of having a whole bulky second pair to carry around. Clip-ons are sleek, thin and lightweight, and can be stored in the same case as the pair they are made for, or a separate case about the size of a phone. Most clip-ons typically use small hooks on the sides to be secured to the frames, but some are specifically made by frame manufacturers for their own line and might fasten using alternate means such as magnets.
Why choose custom clip-ons?
It is very simple to have custom clip-ons made for a frame; there are very few examples of frame styles that shouldn’t or can’t accomodate a clip-on for it. With custom clip-ons, patients can select their preferred lens colour, metal wire colour, polarization style, and even attachment style. Most clips are made from titanium, a light-weight, flexible yet durable material.
Are there any drawbacks to clip-ons?
Just like with photochromic lenses, there are some drawbacks to clip-ons. While clip-ons can be made for almost every style of frame, there are a few that won’t work well. Custom clip-ons have an upper size limit, so oversized glasses are less likely to have clips made for them. Because of the way they hook onto the frame, clip-ons are not advised for semi-rimless and rimless glasses, as the hooks are more likely to scratch the lenses. Finally, clip-ons only fit the frame they are made for, so if something happens to the glasses the clips are made for – they break, get lost, etc. – you are going to need to replace both the glasses and the clips.
Sunglasses for Sun Protection
Of course, you can’t have a discussion about sun protection options without talking about the most obvious choice: an actual pair of sunglasses.
Sunglasses come in a variety of shapes, sizes, styles and colours. From contemporarily fashionable to timeless and sporty, sunglasses have been the ultimate sunshine accessory regardless of whether you require a prescription or not. But more than complimenting your personal sense of style, sunglasses are one of the most important tools for UV light protection.
Designed to filter out harmful UV rays, sunglasses shield our delicate eyes from the damaging effects of the sun’s radiation. By reducing the risk of eye conditions like cataracts, macular degeneration, and photokeratitis, these shades help preserve our long-term eye health.
Why choose sunglasses?
Sunglass lenses can be made to a prescription, can be made with a variety of colours and tint levels, and can have polarization added in to help with light sensitivity and sharp glare reduction. With dedicated sunglasses, you can feel confident in having both your vision correction and your eyes protected from the sun at the same time.
Your sun lenses should be rated for UV 400 protection
Of course, not all sunglasses are made equally. In order to ensure adequate protection in today’s climate, you should make sure that your sun lenses are rated for UV 400 protection, which will provide almost 100% coverage against UVA and UVB exposure. If you are having custom lenses done through your optometrist or local optician, chances are the lenses will be made with UV 400 protection built in as a standard, but it never hurts to ask and make sure. However, if you are simply purchasing a pair of sunglasses off the shelf then it’s best to ask the sales person if they can confirm the level of UV protection in the existing lenses.
Darker lenses don't always equal better protection
The colour of the lens will have no bearing on the protection level; darker does not necessarily mean better in this case, and since darker lenses cause the pupils to expand and take in more light, dark lenses without UV 400 protection actually cause your eyes to absorb more UV light than if you weren’t wearing anything at all. Polarization and UV 400 are also two separate treatments, so you can’t assume that your polarized sun lenses have UV 400 protection built in as well. When in doubt, it’s always best to ask an optical professional.
Whether you decide that photochromic lenses, custom clip-ons or a dedicated pair of sunglasses are the best option for your needs, at the end of the day UV light can be quite damaging to our eyes, and they need protection from UV light. Have a question about which one might be better for you? Pay us a visit at one of our two locations – 360 EyeCare Beaches and 360 EyeCare Rosedale – to speak with one of our eye care professionals.