Note: This post does not constitute medical or health advice. Our goal is to help online ESL teachers learn about the options they have to reduce their exposure to blue light from their digital devices while teaching online. If you are experiencing any symptoms pertaining to your eye health, or any other health matter, please consult a qualified medical professional.
Do Blue Light Blocking Glasses Really Work?
The jury is still out on whether blue light blocking glasses provide any benefit. Nonetheless, with all of the hype about the effects of blue light on our health, their popularity has grown significantly. Let’s begin with the basics before deciding if blue light blocking glasses are worth your while.
What is Blue Light?
You’ve been hearing a lot about blue light, and the possible effects it has on our health. What you may not realize is that while many people associate blue light with the light emitted from their computer, tablet, and smartphone screens, the main source of blue light is the Sun. In fact, our devices account for a very small fraction of the exposure we have to blue light.
The Sun produces a wide range of both visible and invisible light. According to Prevent Blindness:
In our homes and lives, other sources of blue light include:
- Fluorescent lights
- Compact Fluorescent light (CFL) bulbs
- LED lights
- Flatscreen LED TVs
- Screens on computers, tablets, and smartphones
Is Blue Light Bad for You?
Blue light itself isn’t bad for you. Indeed, there are benefits to our health from blue light. It regulates our circadian rhythm – which is our body’s natural body clock. It impacts our mood, our alertness, and memory function during the daytime. In essence, it plays a significant role in keeping us awake, alert, and active during the day. A lack of exposure to blue light can lead to a range of health issues. So, blue light is both necessary and beneficial to our health.
On the other hand, concerns that increased exposure to blue light beyond natural levels is impacting our health in harmful ways, particularly due to extended periods of use of electronic devices, LED lights, and other sources. Some studies suggest a link between exposure to light at night, such as working the night shift, to some types of cancer, diabetes, heart disease, and obesity. These concerns clearly go beyond the common concerns many people have about the possible effects blue light has on our sleep and eye health.
What are Blue Light Blocking Glasses?
Blue light blocking glasses are eyeglasses that are designed to filter out blue light before it reaches your eyes. They work by filtering out high energy visible (HEV) light. Blue light blocking glasses aren’t actually new – some gamers and heavy computer users have been using them for some time now. But, as more people become aware of the potential hazards associated with increased exposure to blue light, blue light blocking glasses have entered the mainstream.
Not all blue light blocking glasses in the market actually block blue light, so it’s important not to be duped into thinking that you’ve got blue light blocking glasses just because the manufacturer or vendor says so. As the saying goes, you get what you pay for, and that’s also true for blue light blocking glasses to a large extent. They are not regulated by the FDA because they are not marketed as medical devices.
Do Online ESL Teachers Need Them?
If you are an online teacher who teaches during times when people usually sleep in your time zone, you may be interested in wearing blue light blocking glasses, mainly to improve your sleep and wake cycles. The theory behind this is that by wearing them, you will block blue light from reaching your eyes in the evening and night, when our bodies are accustomed to low exposure to blue light.
Dr. Cathy Goldstein, an associate professor of neurology at the University of Michigan Sleep Disorders Center, suggests that blue light blocking glasses can be useful at night, when blue light from screens can disrupt our sleep patterns. She refers to a growing body of research that supports the claim that blocking blue light before bed can improve sleep quality, and one study in 2009 in particular, which showed that participants who wore blue light blocking glasses before bedtime reported better sleep quality and mood than those who didn’t.
Dr. Rahul Khurana, a spokesperson for the American Academy of Ophthalmology, seems to disagree, and even posits that preventative measures may be more harmful than the blue light itself. Instead, Dr. Rahul suggests limiting screen time, taking periodic breaks from the screen, and occasionally focusing your eyes on objects further away.
According to Dr. Matthew Gardiner, an ophthalmologist at Massachusetts Eye and Ear, there’s no research to suggest blue light damages your eyes. Says Gardiner, “If you feel more comfortable, then that’s fine, but it does not do anything for the health of your eyes.”
You may not need blue light blocking glasses, and there’s still clearly some debate about whether they actually provide the purported benefits. Many people who wear them report having reduced strain on their eyes, better sleep, and other improvements. But research to date has not produced conclusive evidence to suggest that blue light blocking glasses actually help with eye strain, eye fatigue, or lack of sleep.
The lack of conclusive evidence does not mean they don’t help. It just means there isn’t enough evidence to prove they do help, or that they don’t harm us in other ways. Some experts argue that increased exposure to blue light itself may not be as detrimental to our health as many people believe.
So, for the moment, you will have to decide for yourself, based on limited research to support the use of blue light blocking glasses, whether to use them, and then assess if they actually make a difference to you personally.
Here are some links to some research in support of wearing blue light blocking glasses:
How to Buy Good Blue Light Blocking Glasses
In the absence of concrete evidence that they provide the purported benefits of improved circadian rhythm and reduced eye strain, we suggest that you only buy blue light blocking glasses if:
- You think you really need them (which you probably don’t)
- You test and prove for yourself that they actually block blue light
- They have a money-back guarantee in case they don’t work for you
- They have broadly positive reviews from verified buyers
How to Test Blue Light Blocking Glasses
The image below is a linear visible spectrum. You will notice that the spectrum appears black on either end, because the light on either side is invisible (ultraviolet on the left and infrared on the right). The colorful range between represents visible light, becoming warmer as you move towards the right end, and cooler as you move towards the left end.
A simple way to test your blue light blocking glasses is to look at this image wearing the glasses. If your glasses are blocking blue light, the blue wavelength should effectively appear black. In other words, your blue light blocking glasses should be deleting the blue component. For this to work, your screen should be able to display RGB, and you should have normal color perception.
You Probably Don't Need Blue Light Blocking Glasses
Now, we know you came here looking for us to recommend the best blue light blocking glasses for online teachers. Unfortunately, we can’t recommend any, because we honestly believe you don’t need blue light blocking glasses. Neither does CBC and the medical professionals they caught up with in this hidden camera investigation:
What about the Many People who Report Benefits Wearing Blue Light Blocking Glasses?
Certainly, a number of people use blue light blocking glasses, many of whom report reductions in eye strain and better comfort while looking at their device screens, and improved sleep. All this points to the need for more research on the use of blue light blocking glasses to validate these claims. So, while we don’t feel online ESL teachers need to wear blue light blocking glasses, clearly not everyone agrees with our point of view.
If wearing a pair while teaching is something you want to try out on your eyes, here are some of the bestselling blue light blocking glasses on Amazon, all under $30:
Bestselling Blue Light Blocking Glasses on Amazon
Remember, we are not recommending anyone buy blue light blocking glasses, and we think there are other measures online ESL teachers can take.
What We Suggest Instead of Wearing Blue Light Blocking Glasses
Before you go buying a pair of blue light blocking glasses though, here is what we suggest you try instead:
- Maintain a healthy, well-balanced diet
- Take time away from your devices (yes, it’s hard, but you can do it – even if you have to work long hours in front of a screen)
- If you are a smoker, quitting smoking is a very good idea, as smoking has been linked to vision loss or blindness
- Try using night mode in your computer after before sunrise and after sunset
Taking Time Away from Your Computer
We can already hear it – the arguments from online ESL teachers that they have to work long hours in front of the computer, causing strain on their eyes. Firstly, you really only need to be concerned about evening and night time hours, and for these times, you can turn on night mode on your computer. It’s free, and you already have it. We’ll show you how in a moment.
If you happen to be teaching online for long periods during your evening or night time hours, here’s how you can take a break from the screen:
- Use the timer on your phone to do a 3 – 5 minute stretch between lessons. This way, you will be doing some light exercise and getting yourself off the screen. You can also do jumping jacks, running on the spot, squats, planks, or any other on the spot exercise. Set up a yoga mat next to your work area so you can do this quickly and easily.
- Do some meditation. With or without a meditation or deep breathing app, it’s really easy to close your eyes and practice deep breathing, even if only for a minute. You can do this right where you sit (or stand) while teaching online.
- Glance away from the screen periodically, even while you are in the middle of an online lesson. Give your eyes a break by glancing away from the screen from time-to-time. Try it. It’s easy.
Use Your Computer's Night Mode
In case you didn’t know, your computer already has a setting that will adjust the light temperature and reduce the amount of blue light emitting from your screen. Don’t worry, if you need to share your screen with your students while teaching online, this won’t affect what they see. The color changes are only visible on your screen.
If You Use Windows 10
In Windows 10, you can navigate into your Settings and turn on Night Light. You have the option to turn it on manually, or schedule it at a certain time each day. You can also adjust the strength of the Night Light, which will essentially adjust your screen to emit warmer colors and reduce blue light.
If You Use a Mac
Mac users can open System Preferences and navigate to the Display settings. Once in the Display settings, click on the Night Shift tab as shown below. You have the option to turn on Night Shift manually, or schedule it to turn on automatically each day. You can also adjust the Color Temperature setting by moving the slider and choosing a warmth that feels comfortable to your eyes.
Control Your Screen Color Temperature Even More
If you aren’t getting the desired warmth from your computer’s built-in night mode setting, there’s a free app called f.lux which you can download and install on your device. There are Windows, Mac, Linux, iOS, and Android versions of the app. Windows users will also be able to control their LED light color temperatures with f.lux with the LED smart bulbs, but these bulbs can also be controlled using Alexa, Apple HomeKit, or Google Assistant.
We know we are not going to have everyone agree with us about the benefits of blue light blocking glasses. We aren’t arguing that overexposure to blue light can potentially be harmful to your health. It’s just that there’s no clear-cut evidence that blue light blocking glasses are going to protect you from anything. By all means, if you would like to give them a go, and see for yourself, we won’t stop you from doing so. But, for most online ESL teachers, we think a combination of healthy eating and habits, exercise, reducing screen time, and using night mode on your computer will provide better results.