Everything you need to know about sunglasses

Why is it important to wear sunglasses?

Sunlight contains harmful ultraviolet (UV) rays that can cause damage to the sensitive structures of the eye. Damaging UV rays can cause pterygiums, pinguecula and damage to the retina.

UV light is broken into three different types: UVA, UVB and UVC.

  • UVA has longer wavelengths and passes through glass easily; experts disagree about whether or not UVA damages the eyes.
  • UVB rays are the most dangerous, making sunglasses and sunscreen a must; they don’t go through glass.
  • UVC rays do not reach the Earth because its atmosphere blocks them.

When should I wear sunglasses?

The short answer: Always!

UV light is most harmful on sunrise and sunset, so remember to wear your sunglasses when driving to and from work. Harmful UV light can also pass through clouds; thus, UV light can damage your eyes on overcast days. Certain conditions can cause more glare, e.g. snow, water or sand. Thus, it is important to wear sunglasses on days that you are exposed to high glare conditions as well. Sunlamps and tanning beds also give off harmful UV light.

Some patients are more prone to damage caused by UV light, e.g. patients who uses photosensitive medicine or patients with age-related macular degeneration or previous cataract surgeries.

How to I prevent UV light from damaging my eyes?

You must wear sunglasses to prevent damage to your eyes. While some contact lenses provide UV protection, they don’t cover your whole eye, so you still need sunglasses.

What are the different kinds of lenses that are available?

Look for sunglasses that protect you from 99 to 100 percent of both UVA and UVB light. This includes those labelled as “UV 400”.

Polarized lenses reduce glare and is highly recommended for people who drive long distances or do water sports, such as canoeing, sailing and fishing.

Mirror coatings (also called flash coatings) are highly reflective coatings applied to the front surface of sunglass lenses to reduce the amount of light entering the eye. This makes them especially beneficial for activities in very bright light conditions.

Gradient lenses are tinted from the top down, so that the top of the lens is darkest. These lenses are good for driving, because they shield your eyes from overhead sunlight and allow more light through the bottom half of the lens, so you can see your dashboard clearly.

Lens colour is personal choice and doesn’t affect how well sunglass lenses protect your eyes from UV light. Grey and brown are popular because they distort colour perception the least.

Athletes often prefer other tints for their contrast-enhancing properties. For example, yellow lenses are popular with skiers and target shooters because they work well in low light, reduce haze and increase contrast for a sharper image.

Darker sunglasses decrease the amount of visible light that passes through the lenses compared with lighter lens tints, but they don’t necessarily provide greater protection from UV rays (which are invisible).

Do children need sunglasses?

Children’s sunglasses are essential. Children are at particular risk because they’re in the sun much more than adults, and their eyes are more sensitive as well. UV damage is cumulative over a person’s lifetime, which means you should begin protecting your child’s eyes as soon as possible.

In fact, the lens inside a baby’s eye allows more UV light to pass through it and reach the retina than the lens of an adult eye. Making sure your baby wears sunglasses that block 100 percent UV and also protect her eyes from high-energy visible blue light may help reduce the risk of macular degeneration later in life that could cause permanent vision loss.

I wear glasses. What options are available to me?

You can buy prescription sunglasses or glasses with photochromic lenses (which change from clear to dark) from your eye care practitioner. 

Which sunglasses will suit me?

Have a look at our guide below to see which sunglass shape will suit your face shape best.

Our friendly staff members are always available to offer advice on frame and lens options.