York Medical Eye Care Blog - Why Is It Important to Wear Sunglasses?

Why Is It Important to Wear Sunglasses?

Dr. Patrick Cheung and Janni Leppanen

Why Is It Important to Wear Sunglasses?

Dr. Patrick Cheung

by Dr. Patrick Cheung and Janni Leppanen| 3 min read

Why Is It Important to Wear Sunglasses?

Sure, wearing sunglasses can look great. But why are they important for the health of your eyes? The most important job of sunglasses is to keep your eyes protected from the sun's harmful ultraviolet (UV) and blue light rays.

We have known for decades that the sun's UV rays can damage the tissues on our skin and in our eyes. The most damaging of the sun's effects on the eyes include cataracts and macular degeneration. The World Health Organization (WHO) states cataracts being the number one cause of preventable blindness in the world. Macular degeneration is the number one cause of blindness North America.

With your vision being paramount in your everyday life, why not wear a pair of great sunglasses to protect your eyes now and in the future?

When purchasing sunglasses, the most basic thing is to look for are lenses that block out 100% of the harmful UVA and UVB rays from the sun. Although most sunglasses will offer this protection, UV protection regulations in Canada are not mandatory. Not all sunglasses will block the full amount of UV light.

If you are wondering if your sunglasses are up to par, UV penetration in a lens can be analyzed with a UV transmittance test. This is a complimentary service that is offered at York Medical Eye Care.

What about blue light?

UV protection has been advocated for years. However, new research suggests that sun damage to your eyes is not just done by UV light.

Blue light is next to ultraviolet light on a colour spectrum, part of the visible colour spectrum. UV light energy goes from 10nm to 400nm, and blue light goes from 400nm to 460nm. Thus, blue light is considered high energy visible (HEV) light. This certain wavelength of light has enough energy to do damage to tissues in your eye. The damage is done specifically to the retina, the inside of your eyes that contain the rods and cones that send light information to your brain. This can cause various problems, including macular degeneration.

Colour spectrum diagram

Some, but not all sunglasses will help protect against UV light as well as blue light. At York Medical Eye Care, we carry multiple lines of sunglasses that offer this blue light protection. Feel free to stop by to learn more about this new and exciting advance in eye care.

How about for children?

Children benefit in many ways by being outdoors. However, many children and parents don't think much about sunglasses. Studies show that sun damage in eyes is actually more harmful to children than adults. About 80% of the sun damage done to eyes in a lifetime occurs before 18 years old. There are multiple factors involved, but partially it is due to the crystalline lens in a child's eyes being more transparent at a young age, and not able to absorb as much UV light.

A hat and sunscreen may be helpful, but they do not protect the eyes nearly enough compared to sunglasses. There are many options for sunglasses that can help protect our children's eyes from the sun. Children's eye exams are covered by OHIP once a year until the age of 19. Come for a visit to see what options can suit you and your children the best.

Can cheap sunglasses be bad for your eyes?

Due to sun protection regulations in Canada not being mandatory, cheap sunglasses may not always have 100% UV protection in them, even if there is a sticker on the lens that says so. If the lenses do not have UV protection in them, they can do more harm on your eyes than good. A tinted lens will make your pupil bigger, allowing more of the sun's harmful UV rays to enter the eye. Always make sure that your sunglasses have UV protection in them. This can be analyzed with a UV transmittance test.

In addition, optical quality in cheap sunglasses may not be ideal for vision. This can cause distortion, blur, and overall strain of the eyes after wearing them a full day. Poor optical quality can be due to the inexpensive type of lens material being used and possible warpage of the lenses in the frame. There are many people that feel like their vision is worse from wearing sunglasses, and this can be caused by poor optics in the lenses.

Your eyes are being used every day, so remember to treat them well and keep them healthy. One of the easiest ways to do this is a good pair of sunglasses. Visit York Medical Eye Care to chat with one of our friendly optometrists or eye care specialists if you would like to learn more about sunglasses and your eyes.

For any questions or if you would like to book an appointment, Dr. Patrick Cheung and the team at York Medical Eye Care can be reached at (905) 836-1112 or