Vision and Sight

Debunking 4 Dangerous Sunglass Myths to Save Your Eyes

Everyone’s got a favourite story about what sunglasses you should buy – but how do you distinguish between fact and fiction to get the best protection for your eyes? Don’t worry! We’re here to help.

MYTH #1:

Woman staring into the sun
It’s never a good idea to stare at the sun

The verdict: False.

The facts: This is never a good idea. Even with quality sunglasses on, the ultraviolet (UV) radiation from the sun is strong enough to cause permanent eye damage if you stare at it for long. Even looking directly at a solar eclipse is hazardous.

Looking at the sun even for just a few seconds can develop sunburn on your eyeball. Of the three types of light the sun produces – visible, infrared, and UV, UV radiation is the most damaging to structures within your eye, especially if it’s reflected off sand, snow or water.

The cells of the cornea (the transparent outer layer of the eye), blister and crack when overexposed to UV light, just like sunburned skin. Doctors call it ‘photokeratitis.’ Symptoms usually appear a few hours after the damage has occurred and include excessive tearing, tissue inflammation and the feeling that you’ve rubbed your eyes with fine grit sandpaper. Luckily, the effect is commonly temporary, dissipating within 36-48 hours.

If you look steadily at the sun for a little longer (i.e. more than 5 minutes), you’re more likely to damage your retina (the collection of light-sensitive rod and cone cells at the back of the eye that transmit images to your brain). Solar retinopathy, as it is known, isn’t usually painful like photokeratitis, but can lead to macular degeneration, partial or complete blindness.

SOLUTION: Never stare directly at the sun. Even if you’re wearing protective sunglasses.  The only safe way to look at the sun is through binoculars or a telescope with a specially installed solar filter.

MYTH #2:

Polarised sunglasses and a computer
How to use a computer to test if sunglasses are polarised

The verdict: False.

The facts: It’s actually very easy to tell if you have polarized lenses.

An easy way to identify whether your sunglass lenses are polarized is to hold out them out in front of you and look through them at a computer screen. Rotate them clockwise to between 60° and 90°. If the lenses are polarized, they will turn to a very dark or black colour.

Another way is hold your sunglasses in front of you towards a reflective surface, such as a glass table or water.  As you look through the lenses, slowly rotate them counterclockwise. If the glare you see through them doesn’t immediately diminish, it’s safe to say they’re not polarized.

SOLUTION: Use either of these methods before purchasing polarized lenses to make sure you’re getting what you pay for.

MYTH #3:

Man driving with sunglasses
Are polarised sunglasses better for driving?

The verdict: False.

The facts: There are multiple benefits to wearing polarized sunglasses while driving during the daytime.

Polarized lenses contain a special filter that blocks intense, direct or reflected light. They reduce glare and haze so your eyes feel more comfortable and can usually see better (unless, of course, you’re driving at night, when the darker lenses will more negatively affect light transmission).

There are 5 generally accepted benefits of wearing polarized sunglasses while driving (during the day):

  • Reduction of road surface glare
  • Reduction of glare reflecting from other cars
  • Reduction of dashboard glare
  • Reduction of headlight reflections from the road’s surface
  • Complete elimination of dashboard reflection on the windscreen.

SOLUTION: Polarized lenses are invaluable while driving during the day, particularly if they’re Category 2 or 3 sunglasses, which means they allow enough light in to enhance driving safety.

Most sunglasses shouldn’t be worn for night driving. Indeed, Category 4 sunglasses should always be avoided for driving altogether, due to their very low light transmission.

MYTH #4:

Sunglasses in winter
Should you wear sunglasses in the winter?

The verdict: False

The facts: Winter sun might not be quite as bright as summer sun, but it can still contain intense ultraviolet light. Coupled with low winter temperatures and dry air, UV light penetration is usually strengthened and sunlight reflected off water or snow can make the UV radiation penetrating your eyes a killer force.

The sun on a cloudy day looks weak, but is frequently associated with strong UV rays. When it’s sunny, your pupils naturally constrict, slightly restricting UV entry into your eyes.  But, during cloudy days, your pupils tend to dilate more, which in turn lets more UV in, potentially causing greater damage to your retina and exposing you to the risk of retinal disease.

Additionally, while direct sunlight can be very damaging to your eyes, reflected UV rays are potentially even more dangerous. Grass and soil reflect less than 10% of UV radiation, but sand may reflect 15%, sea foam 25%, other water surfaces up to 40% and snow up to 80%.  And, because you’re more likely to look downwards, more UV light can be reflected directly into your eyes.

SOLUTION: Ensure your eyes are well protected during winter periods or on cloudy days. Always wear quality sunglasses with 99-100% UV protective lenses.

Did you miss our previous article on sunglasses myths? Now Exposing the Top 3 Sunglasses Myths before You Buy or watch the video below: