What are blue light glasses? Blue light glasses, also known as ‘blue-light-blocking glasses’ filter out blue light rays emitted from digital screens. There’s often a yellow tint on the lens of blue light glasses, and they may or may not have a prescription.
This article will explain what blue light glasses are, what blue light is, how and if blue light glasses work, and the positive and negative effects of wearing them.
What is blue light, and is it harmful?
This diagram illustrates the light spectrum from the ultraviolet and visible light part of the electromagnetic spectrum. This spectrum is the light energy that we are concerned with day-to-day for our personal health & safety. Further in this article, we will be referencing different parts of the light spectrum. For context, you may find is helpful to scroll back to this diagram as you read on.
Blue light tells your brain to limit the usual melatonin production for this time of day, which in turn inhibits the feeling of sleepiness.
UV or Ultraviolet light is the part of the electromagnetic spectrum responsible for giving humans sunburns.
To help make it easy to understand, we’re showing hard lines with neatly divided ‘types’ of light. In reality, it is all the same light, just at different wavelengths. The wavelengths have a continuous change in length across the spectrum.
What produces blue light?
Blue light is all around us. The sun emits blue light, and fluorescent lights are sometimes a significant blue light source. The standard old-school incandescent light bulbs do not emit significant levels of blue light. Newer LED style bulbs come in warm or cool light colour variations. The warmer ones will have less blue light than the cooler coloured ones.
Most significantly in the past decade, computer & laptop screens, flat-screen TVs, cell phones, and tablets all use technologies with high amounts of blue light.
The next time you’re scrolling through Instagram for hours, remember that you’re also exposing your eyes to blue light. This raises the question, ‘how does this blue light affect you?’
What is blue light?
Electromagnetic energy is all around us. Most electromagnetic energy is invisible, but a small band of waves known as visible light, are detectable to the human eye. This is what we commonly call “visible light”.
Visible light wavelengths vary from 380 nanometers (violet light) to 700 nanometers (red light). The longer the wave, the less energy it transmits.
Blue light is short, high-energy waves that are slightly longer and less powerful than ultraviolet (UV) waves.
Health experts have warned against the harmful effects of UV rays, which can damage your skin and your eyes. High-energy blue light waves also have impact on our health, but in a different way than ultraviolet light. It should be noted that there are both positive and negative effects of blue light. More detail on this below…
Is blue light harmful to your eyes?
Some health experts are concerned about the harmful effects of blue light since people spend so much time on their digital devices at such a close range. If you search the internet, you will find opinions that blue light can have direct harmful effects on your vision. Often mentioned is that blue light is a contributing factor to macular degeneration. However, other sources will claim the opposite, saying that blue light does not contribute to vision disease such as macular degeneration. So, what gives? Let’s clear this up for you:
There is research that concludes that high-intensity blue light can be harmful, contributing to macular degeneration. This one, for example: https://www.nature.com/articles/s41598-018-28254-8#Abs1
However, this refers to high-intensity blue light from sunlight. Most research on the effects of artificial blue light sources does not suggest that these sources directly harm your eyes. It should be noted that because continuous daily use of blue-light emitting devices is relatively new, data is still limited for effects throughout a lifetime.
When reading about blue light research, it is important to distinguish between the powerful natural sunlight, and the lower intensity blue light from common electric and electronic devices. Same light. Different levels of intensity. However, there are still some other considerations around your health and blue light exposure from your daily use of devices and computer screens. Read on for more on this.
Positive and negative effects of blue light
Now that we have cleared up the confusion of how blue light is reported and both harmful and not harmful depending on the context around the research, let’s take a look at the positive and negative effects of blue light.
Positive effects of blue light
There are certain health benefits from blue light, and they include:
Help you stay alert
Studies show that blue light can help you stay alert, increase reaction time, and keep you awake when you’re not at your peak performance time of day.
Boost memory and cognitive function
A 2017 experiment involving participants who had a 30-minute blue light “washout” period performed better on verbal memory and memory consolidation tasks afterwards. Study participants who had an amber light “washout” didn’t perform as well.
Treat certain skin conditions
Many studies show that blue light eradicates acne-causing bacteria and reduces inflammation in acne breakouts.
There are devices used by estheticians and sold for at-home purposes which utilize blue light therapy to achieve clearer skin. Dermatology is outside our scope of expertise, but this came up in our research, and it seemed worth mentioning. For more information on this, consult your local dermatologist.
On the same note, blue light is also reportedly used to treat skin conditions such as Actinic keratosis, plaque psoriasis, and basal cell carcinoma tumours.
Help you maintain a healthy sleep/wake cycle
The natural day and night cycles from sunlight are used by our body to signal hormone management that helps us feel sleepy or wake up regularly. For us in Canada further from the equator, this isn’t a perfect system, as our daytime is much longer in summer and shorter in winter. But in general, the natural day and night cycles is a contributing factor to our health by helping us maintain regular sleep schedules.
Negative effects of blue light
Now that we’ve discussed the importance of blue light to maintain a healthy sleep cycle, let’s take a look at some of the ways blue light is having a negative effect on you.
Blue light and digital eye strain
Staring at your phone for extended periods can cause digital eye strain. Research shows that people who use digital devices tend to blink less often, and therefore, their eyes may be strained from the lack of moisture.
Digital eye strain can cause different symptoms for different people. If you’ve experienced digital eye strain, you may notice:
- dry eyes
- sore or irritated eyes
- tired eyes
- headaches
- facial muscles fatigued by squinting
There may be limited permanent damage from digital eye strain, but there are secondary issues to consider. Dry eyes can cause a person to rub their eyes often. Excessive rubbing of one’s eyes can result in permanent damage to the retina and cornea.
Blue light and sleep
While there is no evidence of the long-term effects of blue light on human eye health, blue light is shown to affect your sleep-wake cycle.
Your body has light sensors in your eyes and skin to signal when the day begins and ends. At night, the sensors in your eyes prompt your body to release melatonin, the sleep-inducing hormone.
Researchers have found that blue light in the evening hours decreases melatonin production and delays or disrupts your sleep cycle, thus leading to insomnia or poor sleep quality.
When blue light disturbs your sleep cycles, the following problems can also develop:
- an elevated risk of hormone-related cancers
- lower levels of leptin
- metabolic changes, especially blood sugar
How should I manage my exposure to blue light?
There are a few things you can do to manage exposure to blue light, and they include the following:
Have set times for when you’re on and off your devices
Even when you’re at work, it’s a good idea to take a break every thirty minutes from your digital screen time. Taking a break will allow your eyes to recover and prevent digital eye strain.
Some people suggest staring at a distant object for 30 seconds before returning to your screen. Taking a short walk is also a great way to decrease back and shoulder pain.
Keep your eyes lubricated
Eye drops and room humidifiers are ways to help keep your eyes moist. Any drug store should carry eye drops that prevent dryness and irritation.
Adjust the blue light on your screen
Most phones or computer screens have “night mode,” where the screen will emit warmer tones. You can also buy blue-light-filtering screens or phone or computer apps that filter out blue light.
However, filtering out blue light does not mean that being on your phone during bedtime will not disrupt your sleep. It is still better to turn off all digital screens before going to bed.
Blue light glasses are effective in blocking out blue light
Many studies have proven that blue-light glasses effectively filter out blue light and decrease blue light exposure. We will get into more detail about blue-light-blocking glasses, what they are, the science behind them, the positives and negatives, and more.
What are blue light glasses, and can they protect against blue light?
Now that you understand what blue light is and how it affects you, let’s take a look at how blue light glasses can help, and how effective they are.
They have filters that block or absorb blue light and, in some cases, UV light. These glasses help reduce exposure when looking at a digital screen. They’re worn during the day while working in front of a computer and at night to prevent the blue light from screens from keeping you awake.
Although researchers are still working to figure out the long-term effects of blue light, blue light glasses, along with certain lifestyle choices, blue light blocking lenses can help you manage things like dry eye and eye fatigue.
With all that said, do blue light glasses work?
- Yes, if your goal is to reduce eye strain and control the times of day when you expose your eyes to blue light to help maintain healthy sleep cycles. Some studies have shown that blue-light glasses provide a viable treatment for preventing melatonin suppression and increasing sleep quality. Notably, wearing blue light glasses is not a silver bullet, and should be used together with other solutions such as using night mode on your screens.
- No, if your concern is light rays from devices increasing risk of macular degeneration.
- Yes, if your concern is to reduce contribution of macular degeneration from sunlight exposure. However, in this case, blocking blue light is not enough. You should be most conserved about the higher energy UV rays in this case. Your best option is to wear broadband UV blocking sunglasses when you’re enjoying a sunny day.
How do blue light glasses work?
Now that you know that blue light glasses work as part of a complete solution to manage the effects of blue light, you probably wonder how they work. Let’s break down the design of blue light glasses to get a clear understanding.
Micro-layer technology
Blue light lenses are made with ‘micro-layers’ in the lens’ construction. These micro-layers alter how light is transmitted or reflected. Blue light lenses are engineered to absorb or reflect a specific group of wavelengths. These wavelengths are usually between 380 to 450 nm (nanometers).
Anti-reflective coating
Blue light lenses sometimes incorporate an anti-reflective coating, which employs a method of lightwave control called ‘destructive interference’ to cancel out some wavelengths of light. The result is less visible reflection, which enhances eye comfort further when combined with blocking blue light rays.
Are blue light glasses bad for your eyes?
Even without conclusive evidence for the effectiveness of the benefits of blue light lenses, there is no evidence suggesting they are harmful to your eyes.
Are blue light glasses safe for kids to wear?
Blue light glasses are safe for everyone, including children. Kids are using digital devices more often than ever. Whether playing a game or watching on Youtube, encouraging your kids wear blue light glasses may be a good idea for their overall health.
When should you wear blue light glasses?
Should you wear blue light glasses all day?
Although it is acceptable wearing blue light glasses all day, it’s not necessary to do so, and remember, moderate blue light exposure during the day is beneficial for overall health. Some of these positive effects include improved memory and cognitive function.
Can you wear blue light glasses outside?
You absolutely can wear blue-light-blocking glasses outside. The most significant source of blue light is sun exposure. There are blue-light-blocking sunglasses that you can wear to protect your eyes from both UV and blue light.
Should you wear blue light glasses when watching TV?
Like any other digital device that utilizes LED technology, TVs are also a source of blue light. So if you’re watching TV before bed or for long periods, you should slip on your blue-light filtering glasses. The screen image may appear yellowish when initially putting on your blue light glasses. After a few minutes, your brain will adjust, and you likely won’t notice the adjustment anymore.
Can you wear blue light lenses while wearing contacts?
As long as your blue light glasses do not have a prescription, you can wear them while wearing contacts.
Choosing the right blue light glasses for you
Can I get prescription blue light glasses?
If you have limited eyesight or are currently wearing prescription glasses, you may need blue light glasses that have a prescription.
To do that, you can drop by our eyewear gallery or book an appointment at our clinic.
What style do I want?
Like any other pair of glasses, there are hundreds of frames available. Even though there is a yellow tint to blue light glasses, they’re actually quite stylish.
Check out our bolg post on some eyewear trends here https://www.eyeexpressions.ca/trendy-eyewear-for-winter-2021/ so you can rock the hottest styles!
What level of protection do I need?
Knowing how much exposure you have to blue light will determine the level of protection you need. We offer a variety of styles and levels of vision protection.
Are blue light glasses worth it?
Blue light is unavoidable since we’re surrounded by it. Blue light exposure has positive and negative effects, whether from the sun or your smartphone.
The positive effects include increased cognitive function, improved memory, stimulated alertness, and even improved skin complexion. The adverse effects include eye strain and causing people to have trouble falling asleep.
There needs to be more research around blue light glasses, but many have shown that blue light glasses effectively block out blue light; therefore, the hype around blue light seems to have merit.
Although blue light glasses may help with digital eye strain and help you fall asleep, they are only one component of a complete solution. It is recommended to include other lifestyle choices to protect your vision and overall health. Some of these things include reducing screen time, taking breaks during work, using a reduced blue light screen setting, and turning off your phones before bedtime.
Before purchasing your blue light glasses, talk to an optometrist to choose the best option for you.
If you have more questions or need help choosing the right pair, contact us.
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