Protect your eyes
Sunglasses are a first line of defence against eye damage caused by UV light and also offer protection against blue light filtering through the atmosphere.
Sunglasses are more than a fashion accessory. They’re a first-line defence against eye damage caused by ultraviolet (UV) and blue light filtering through the atmosphere. To protect your eyes, wear good-quality sunglasses and let fashion sense meet vision care.
Ultraviolet light, the invisible part of the light spectrum, comes in two forms: UVA and UVB. Both can be absorbed by the eye in much the same way they’re absorbed by the skin. While you can’t see or feel the effects of UV rays right away, by the time you reach your fifties, the eye damage they cause is permanent.
Blue light, found in the blue portion of the colour spectrum, can also harm vision. The glare from this intense light impairs the eye’s ability to focus properly. Health Canada warns that recurrent exposure to blue light—for example, in light reflecting off snow or water—promotes premature aging of the retina and increases the risk of becoming blind.
Different light, different damage
As the eye absorbs light, heat is generated and a chemical reaction takes place in the eye tissue. Prolonged exposure to both UV and blue light over time overwhelms the eye’s natural ability to heal itself, leading to permanent damage.
The type of damage to the eye depends on the type of light.
Who needs protection?
Everyone who works or plays in the sun needs eye protection. If you’re taking photosensitizing drugs, you have to be even more careful. Older people and those with lighter-coloured eyes are more at risk because they have less melanin, which acts as the body’s natural sunscreen protection.
Working with computers and/or under bright fluorescent fixtures can also damage eyes. For indoor use, wear sunglasses with an invisible UV protective coating that has a clear lens colour.
We’re exposed to harmful UV light on overcast and hazy days, not just sunny ones, so grab your sunglasses and protect your eyes.
Levels of sun protection
When choosing sunglasses, look for those that offer proper UV and blue light protection for the level of sunlight and your activities. Use Health Canada’s three grades of sunglasses to select the best type. Keep in mind that labelling standards are voluntary.
Amount of light blocked
from 0 to 60 percent of visible light and UVA rays; between 87.5 and 95 percent of UVB rays
for mild sunlight; not recommended for driving
from 60 to 92 percent of visible light and UVA rays; between 95 and 99 percent of UVB rays
for stronger sunlight; good for driving because they block reflected glare
up to 97 percent of visible light; up to 98.5 percent of UVA rays; at least 99 percent of UVB rays
best for prolonged exposure to sunlight; not good for driving as they can reduce vision
Note: some sunglasses are now labelled UV400; they offer full protection against UV rays.
Tips on choosing the right sunglasses
Once you’ve decided on the level of UV protection, check out the type, quality, and colour of the lenses.
Already wear prescription glasses? Consider photochromic lenses, which react to the sun’s intensity by automatically darkening, creating built-in sunglasses.