Sunglasses are more than just a fashion statement: wearing a good pair of shades is one of the most important things you can do for your eyes. If your eyes are unprotected, UV rays can damage them, increasing your risk for eye disease later in life. If you’re confused about mirror coatings, polarized lenses, lens colour, the difference between cheap and inexpensive sunglasses, read on to find out the answers!

Do darker sunglasses (that you can’t see my eyes through) protect from UV rays better than lenses that are lighter in colour?

No. Dark lenses don’t necessarily provide more UV protection than lighter shaded ones. While darker-tinted lenses are appropriate for very bright conditions (or from people whose eyes are more sensitive to light), experts recommend medium-tinted lenses for day-to-day use.

Does it matter what lens colour I choose?

Yes. For the best colour perception, lenses should be grey, amber, brown, or green. Green lenses are recommended for ordinary, day-to-day use as they offer good colour contrast and minimal colour distortion. Red, orange, blue, or purple tints can cause colour distortion and let in too much light.

Do I need expensive sunglasses or are inexpensive ones just as good?

You don’t need expensive shades. Look for a label or tag indicating the level of UV protection. A cheap pair of sunglasses offering a high UV protection is a safer bet than an expensive pair with low UV protection.

What percentage of UV protection should I look for in sunglasses?

There are two kinds of UV rays: UVA and UVB. We recommend shades that block 99 to 100 per cent of UV radiation—and make sure that includes both UVA and UVB. If you buy a pair of sunglasses that don’t block UV rays, you could be doing even more damage to your eyes. Sunglasses that just shade your eyes without adequately blocking UV radiation can cause your pupils to dilate in the sun, allowing in more rays.

What is the best style of sunglasses to protect my eyes?

Large-framed, close-fitting, wraparound shades offer the best protection. The lenses should be big enough to shield your eyes from all angles (above, below, left, and right), and block light coming in around the frames. If you wear shades while playing sports, make sure the lenses are made from shatter-resistant polycarbonate, not glass.

When should I wear my sunglasses? What about children?

You should wear them anytime you are outside—winter or summer—and experiencing sunlight or reflected light (for example from water or a ski hill).

Anyone who spends a great amount of time outside at work or play should be particularly alert. Shades are also recommended for people who have had cataract surgery or who take certain medications, such as tranquilizers, sulfa drugs, or birth control pills, which can increase the sensitivity of your eyes to light.

Children who play outdoors should also wear sunglasses. Children’s shades should be impact-resistant, with bendable frames and unbreakable, polycarbonate (not glass) lenses.

With UV exposure, your risk of eye disease builds over time. The more UV rays your eyes absorb over your lifetime, the greater your risk of conditions such as age-related macular degeneration (AMD) and cataracts later on. Taking steps now can really pay off down the line.

What are polarized lenses for?

This type of lens blocks glare caused by reflection from flat surfaces. For this reason, they are recommended for driving, boating, fishing, skiing, or any other activity where there is a chance of glare from water, snow, or the ground.

What about photocromatic lenses that lighten or darken in response to UV light? Are they sufficient in bright conditions?

Yes, they are sufficient for bright conditions. However, bear in mind that photocromatic lenses take a few minutes to lighten or darken when going from one light situation to another.

What about lenses that clip on to my existing glasses? Do they work?

Clip on sunglass lenses are worn over top of your prescription glasses. While handy, clip-ons might not fully.