Do blue light blocking glasses work?
As the time we spend in front of a screen has increased, so has our exposure to the blue light emanating from our devices like laptops, tablets and mobile phones — and our bodies have felt it.
Blue light is linked to eye strain, including related symptoms like headaches, shoulder and back pain, in addition to sleep problems. There’s even some concern that too much exposure to blue light could cause damage to the retina at the back of the eye. As a result, blue light glasses that claim to reduce or stop these problems have rapidly risen in popularity.
However, researchers are still determining exactly how much damage blue light does, particularly blue light emanating from digital screens. Because this information isn’t yet conclusive, some marketing claims about what blue light blocking glasses can accomplish are a little suspect, leading many consumers to wonder if blue light glasses really work.
Still, to determine if these glasses are right for you, read on for more information about blue light’s currently known effects and exactly how the best blue light blocking glasses can protect you.
Should I be concerned about blue light?
Claims about the damage caused by blue light typically fall into three categories: visual strain, sleep disruption and retinal damage, specifically macular degeneration. However, the research linking blue light, specifically from screens, to some of these problems isn’t yet conclusive. So, whether blue light blocking glasses work depends on what you expect them to accomplish.
Here’s a more in-depth look at some of the claims surrounding blue light blocking glasses.
Blue light plays a role in digital eye strain
Reports of dry, red, irritated, fatigued eyes while using screens are so prevalent there’s a term for it: digital eye strain. This problem is multilayered and isn’t just about blue light. When using screens, we tend to blink less, causing dry eyes and eye strain.
Blue light really does negatively impact your sleep
Your body’s natural sleep and wake cycle, the circadian rhythm, is disrupted when using a computer, tablet or phone before going to bed. The blue light of a digital screen mimics the blue light of the sun. But when that blue light is hitting your eyes at night, it tricks your body into thinking it’s still daytime and suppresses the production of the sleep hormone melatonin.
Research shows that people who use electronics at night take longer to fall asleep, spend less time in restorative REM sleep and feel subjectively more tired than those that do not. One study also showed that blue light blocking glasses worn two hours before bedtime improved sleep and the participants were more engaged, productive, helpful and positive at work.
While experts recommend putting down your phone two to three hours before bedtime, Americans don’t do it. According to the National Institute of Health, 90% of Americans spend at least a few nights per week on electronics within an hour of bedtime. So if the screens-before-bed habit isn’t going away, blue light blocking glasses offer a clear alternative solution.
Blue light may damage your eyes
The claim that blue light causes retinal damage or macular degeneration is not yet proven. While some laboratory studies conducted on cells in a petri dish or on animals showed a link, they did not mimic the natural conditions of blue light exposure to a live human eye or use blue light from digital screens, according to the American Association of Ophthalmologists.
Any harm done to a human retina by high-energy light like blue light is thought to be cumulative. Every source, like the sun, digital screens and LED lights, may compound the damage. Prolonged exposure to ultraviolet light is known to cause harm to skin and eyes — but we don’t yet know what similarly prolonged exposure to blue light from screens can do.
What is blue light, anyway?
Blue light isn’t confined just to screens — it’s all around us. Blue light is found in traditional fluorescent lights, compact fluorescent light bulbs and LED lights, but blue light’s primary source is the sun. And, not all blue light is bad. The sun’s blue light gives us energy, helps us stay alert during the day, aids in memory and cognitive function and elevates mood.
But some blue light can be harmful. On the spectrum of visible light, each color of light has a particular wavelength — it’s what makes red look red and blue look blue. The wavelengths range from 380 nanometers (nm) on the blue end of the spectrum to about 700 nm on the red end. The smaller the number, the shorter the wavelength, Shorter wavelengths have higher energy and therefore more potential for damage.
Blue light itself ranges from 380 to 500 nm. Sometimes, blue light is further broken down into blue-violet light (380 to 450 nm) and blue-turquoise light (roughly 450 to 500 nm). Researchers from the National Institute of Health claim that peak light damage occurs around 440 nm. Blue light glasses can help mitigate or reduce some of this damage.
How do blue light blocking glasses work?
Blue light glasses have specially crafted lenses that block a certain amount of blue light. The amount and wavelength of blue light that is blocked varies among glasses. When you consider purchasing blue light blocking glasses or coatings on prescription glasses, it’s essential to understand how much and what kind of blue light your glasses are supposed to stop.
There are clear and amber-tinted lenses available. The clear lenses block only a portion of the blue light spectrum (about 400 to 440 nm), typically around 20% to 40%. However, since these shorter wavelengths are likely the most damaging, that may be all you need. Amber blue light glasses block more blue light (from about 400 to 480 nm) — some are even 100% blue light blocking glasses — but the dark amber may significantly affect your color vision.
Clear blue light blocking glasses are typically more cosmetically appealing, but they may not provide enough protection. How much protection you need varies depending on your situation. If you spend more time looking at digital screens at night, you may want more protection. Or, if you already experience digital eye strain and associated symptoms like eye fatigue, burning or itching eyes, blurred vision, headaches, back and shoulder aches or sleep problems, consider glasses that block more blue light.
While it doesn’t currently appear that blue light causes real retinal damage, our extended use of phones, computers and tablets is new, and therefore the long-term effects of all this screen time are still unknown. As people live longer, and because the effects of exposure are cumulative, being proactive about protecting your eyes could be a smart move.
How to test blue light blocking lenses
You may want to check your blue light blocking glasses using an at-home test. There are many found on the internet. Most of these tests are designed for lenses that block nearly 100% of blue light. These tests are simply not sensitive enough to determine the effectiveness of most clear blue light blocking lenses. If you have top-rated blue light blocking glasses, or a blue light blocking coating on your prescription glasses, don’t be surprised if your glasses fail these tests. Failure does not mean they are not effectively blocking the blue light wavelengths they were designed to stop.
The only way to accurately test blue light glasses is with a visible spectrometer, a pricey device that wouldn’t even typically be found in an eye doctor’s office.
That’s why it’s so important to pay attention to the kind of blue light your blue light blocking glasses are protecting you from when you purchase them. Because they’re blocking the most problematic wavelengths, clear or nearly clear glasses that block the blue-violet range of blue light (380 to 450 nm) can be almost as effective at protecting your eyes as glasses that block a larger percentage of blue light.
Blue light blocking computer and reading glasses
If you are in the market for blue light blocking glasses, you can find plenty of options that are also either computer or reading glasses. The blue light blocking version of these glasses can improve how you see or read a screen and provide the benefits of blue light blocking coatings.
Blue light blocking computer glasses
Computer glasses are designed for wearers to see a computer screen, which typically stands between 20 and 26 inches from the face. This distance is generally considered “intermediate vision,” tending to fall between the ranges corrective prescription glasses use to correct near or distance vision.
Either off-the-shelf or prescription computer glasses can significantly improve digital eye strain symptoms and reduce blurred vision when looking at a computer screen. Because these glasses are designed for use with a computer, they should also block blue light. You can ask your eye doctor to explain your options when ordering a pair of computer glasses.
Blue light blocking reading glasses
Reading glasses or “readers” are designed to help people who spend a lot of time reading on a computer, tablet or e-reader. They offer the magnification that people are looking for in reading glasses, coupled with blue light blocking abilities.
Typically, they also have anti-glare coatings to reduce glare further and make it easier to read. Unless you exclusively use reading glasses to read paper books, ensuring your reading glasses block blue light adds another benefit.
Blue light blocking prescription glasses
A blue light blocking coating added to your prescription glasses can provide a similar benefit. If you already use glasses when looking at your computer screen, you can ask your eye doctor to add this coating, which is similar to an anti-glare or anti-reflective coating.
Be sure to ask your eye doctor which wavelengths blue light blocking prescription glasses affect so you understand the kind of protection you are getting.
Blue light blocking glasses for kids
Just like adults, kids and teenagers are using screens more both at home and at school — in many cases much more than adults. They are just as susceptible as adults are to the damage blue light can cause.
Kids will spend more of their lives looking at screens than any generation before them. Since damage from blue light is cumulative, kids’ blue light blocking glasses or blue light blocking lenses on their prescription glasses can help them just as much as, if not more than, adults.
If your child already wears glasses, adding a blue light blocking coating can be an easy way to help with circadian rhythms, and eye fatigue and strain.
If your child doesn’t wear glasses, they may enjoy picking out and wearing stylish kids’ blue light blocking glasses. But if your child doesn’t like wearing glasses, you can try blue light screen filters that fit over monitors, phones or tablets.
The best blue light blocking glasses for you
While there is still mixed data on the effects of blue light, blue light blocking glasses may provide some level of symptom relief and protection from cumulative blue light exposure.
If you are experiencing digital eye strain symptoms, have trouble sleeping after looking at a screen or spend most of your day in front of a screen, consider blue light glasses. While these glasses’ prices can vary, many cheap blue light blocking glasses do effectively reduce the effects of blue light from digital screens.
Before buying good blue light blocking glasses, consider how much time you spend on screens, particularly at bedtime. Think about what you do while using screens (working, gaming, reading, watching movies) and what you are primarily hoping to achieve by wearing blue light glasses. This will help you decide what type of glasses you want and the level of protection you desire.
READ NEXT: 5 ways to reduce computer eye strain
Page published in February 2021
Page updated in September 2021