Blue Light – What Is It And What Do I Need To Know?

Blue light blocking lenses are probably the hottest trend in eyewear right now. All of the Tom Ford frames we carry are coming from the factory with blue light blocking demonstration lenses already in them, and ads for non-prescription blue light blocking glasses are everywhere. But are these lenses just about fashion or are there some tangible benefits to wearing them?

What Does Blue Light Blocking Mean Anyway?
As anyone who has ever seen a rainbow knows, light is made up of a range of colours that correspond to different wavelengths. The short wavelengths of light look blue to the human eye. Blue light blocking lenses selectively filter out a percentage of this short wavelength light. Removing some of the blue light can make the lenses look a bit yellow and gives the world a slightly yellowish cast when you wear them. The amount of blue light blocked varies between lens manufacturers, but generally the greater the yellowing effect the more blue light is being removed.

Blue Light is Everywhere These Days
While the sun is by far the most powerful source of blue light on Earth, we are exposed to more blue light indoors now than we used to be. That’s because LEDs, some fluorescent bulbs, and all digital screens emit much more blue light than the old incandescent bulbs that used to illuminate our homes and workplaces. While computer, tablet, and cell phone screens are only about one quarter as bright as a typical light bulb and at least an order of magnitude less bright than the sun, they still wind up delivering a fair bit of blue light to our eyes because of how close they are.

Why Should I Care About Blue Light?
Research generally shows that our circadian rhythm (the internal clock that tells us when it’s time to sleep or be awake) is more sensitive to being disrupted or reset by blue light than by other colours. As such, heavy blue light exposure before bed might sabotage your sleep schedule.

Anecdotally, many people also experience eyestrain and / or headaches when they are exposed to large amounts of blue light from artificial sources for prolonged periods of time. Common culprits here are high colour temperature (i.e. bluish-white) LED and fluorescent light fixtures at home or in the workplace or hours upon hours of computer and cell phone usage over the course of the day.

Wait, Somebody Told Me Blue Light Damages Your Eyes
While there has been some theoretical discussion about whether excessive blue light exposure poses any risks to eye health over a person’s lifetime, there is no good evidence that this is indeed the case. In fact, a British optical chain was fined in 2017 for claiming otherwise in an advertisement for their blue light blocking lenses. Ultraviolet radiation from the sun has been linked with an increased risk of developing cataracts and macular degeneration later in life, and while blue light is close to ultraviolet on the electromagnetic spectrum most researchers don’t feel that blue light carries the same risk. Remember, the sun is 20-30 times brighter than your computer monitor. Also, all that time spent staring at a digital screen is time that you are probably not spending outside being exposed to ultraviolet radiation, so lots of screen use may actually result in a net decrease in risk.

So Blue Light Blocking Glasses Are Going to Solve All My Problems?
No, but they might help some of them. A small study at the University of Toronto in 2013 suggested that blue light blocking glasses were somewhat beneficial in reducing sleep disruption and improving performance in nurses working rotating shifts. Also, many (but not all) people find that they develop less eye strain if they wear blue light blocking glasses when on their computer for long periods of time. This likely explains why there are over 50,000 listings for non-prescription “gaming glasses” on Amazon right now.

I Don’t Want to Wear Glasses! Is There Anything Else I Can Do?
Absolutely! Try the following:

  • Move your monitor, phone, or tablet a bit farther away. The amount of light reaching your eyes increases exponentially as the source gets closer.

  • Turn the screen brightness down. This reduces the amount of all light being emitted by the device, including blue.

  • Turn on Night Shift (on a Mac or iPhone), Night Light (in Windows 10), the Blue Light Filter (on Android), or download a program called f.lux. All of these are software-based solutions that reduce the amount of blue light emitted by your screen. Sometimes this works even better than wearing blue light blocking glasses because there is a slider to adjust the amount of blue light removed and you can change it for different activities or times of day. For example, a blast of blue light when you first get to work in the morning can actually help perk you up but you will likely want to really dial down the blue late in the evening. Also, it is nice to be able to shut off the blue light blocking effect completely when working on a project that requires accurate colour perception.

  • Replace compact fluorescent bulbs and high colour temperature LEDs in overhead lights with a lower colour temperature alternative (e.g. 2.7K or 3K)

I Actually Don’t Really Care About Any of This, I Just Think Blue Light Blocking Glasses Look Cool
So do we! And we have great news for you – many of our prescription lenses can have a blue light blocking filter added at no additional cost! We can also show you samples of how your lenses will look with the blue light filter applied. Give us a call or book an appointment online today and let’s chat.