It’s important to wear sunglasses that adequately protect your eyes from the sun’s harmful ultraviolet (UV) rays. Of course, you’ll want to buy shades that look good, too. The reason is simple: if you like your sunglasses, you’ll be more likely to wear them. So, don’t underestimate the style factor.
Aside from appearance, here are some important features to look for in sunglasses:
- Blockage of 99 to 100 percent of UVA and UVB rays – This is the single most important type of protection that sunglasses can provide for your eyes. Long-term exposure to UV light can lead to the development of cataracts and other eye growths, including cancer. Most sunglasses that are sold in the U.S. meet this requirement, regardless of their cost.
- Polarization – Polarized lenses can reduce reflected glare from sunlight that bounces off smooth surfaces, such as water, pavement and car windows. While this feature can be helpful for driving, fishing and boating, it is unrelated to UV light blockage. With that said, many polarized sunglasses are also designed to offer maximum UV protection.
- Lens color – A medium shade is most practical for daily wear. For use in mountaineering and other extremely bright conditions, darker or mirrored lenses may be more appropriate. Keep in mind, though, that lens color is unrelated to UV protection.
- Mirror coating – A mirror finish is a thin metallic coating layered over an ordinary lens. This can increase comfort by reducing the amount of light that enters your eyes, but it will not necessarily provide full protection against UV radiation.
- Wraparound style – Large, wraparound sunglasses can help keep sunlight from shining around the frames and into your eyes, which can reduce the benefits of UV-protective lenses.
- Impact resistance – All sunglasses are required to meet impact standards established by the Federal Food and Drug Administration (FDA) for safety. While no lens is truly unbreakable, plastic lenses are less likely than glass lenses to shatter when hit by an object, such as a ball or stone. Polycarbonate plastic sunglasses are particularly durable, but also tend to scratch easily (if you choose this type of lens, look for a scratch-resistant coating).
- Photochromic – A photochromic lens will automatically darken in bright light (in about 30 seconds) and lighten in low light (in about five minutes). Photochromic lenses can also provide UV protection, but keep in mind that it will take time for them to adjust to different light conditions.
- Single gradient – Lenses that are permanently shaded dark on top and lighter on the bottom can reduce glare from the sky but allow you to see clearly below. This makes them particularly useful for driving.
- Double gradient – Lenses that are permanently shaded dark on the top and bottom and lighter in the middle are well-suited for sports and other activities where light tends to reflect upward off of water or snow, such as sailing or skiing.
The experts at Moffitt Cancer Center can provide you with additional information about the cancer risks associated with UV exposure, and how to protect your eyes and skin. If you have any concerns, you can request an appointment by calling 1-888-663-3488 or completing a new patient registration form online.