In recent years, blue light-blocking glasses have become increasingly popular. People swear by the typically yellow- or orange-tinted spectacles to filter artificial blue light emitted from digital devices like computers, tablets and smartphones. But do blue light glasses work?
Sellers of the glasses, which come in prescription and non-prescription varieties, claim they help keep the eyes healthy, reduce eye strain, improve visual performance, and even help people fall asleep, among other alleged benefits.
However, recently, a new study found that blue light glasses may not do much for the eyes at all. In a meta-analysis of existing research on the effects of blue light glasses on eye health, researchers found that there wasn't strong evidence that blue light glasses are effective at reducing eye strain or improving sleep, NBC News reported.
"The new report adds to a growing body of research showing that blue light-blocking glasses are not helpful in easing eye strain symptoms," Dr. Raj Maturi, a clinical spokesperson for the American Academy of Ophthalmology and retina specialist at Midwest Eye Institute, tells TODAY.com.
Is blue light harmful, how do blue light glasses work, and are there any benefits? We spoke to experts to find out.
What are blue light glasses used for?
Blue light glasses are used to filter out this artificial blue light from digital devices, says Maturi. The lenses of the glasses have filters that sellers claim can block or absorb the blue light, so less of it reaches the eyes. Unlike regular glasses worn all day long, they are only meant to be worn when using screens, the experts note.
Blue light has become a buzzword in recent years, Dr. Brieann Adair, an optometrist at NYU Langone Eye Center, tells TODAY.com, especially as people spend more time in front of computers, tablets and smartphones. During the pandemic, the eye symptoms associated with prolonged screen use came into focus, as did speculation about blue light’s impact on the eyes.
"Blue light is part of the natural, normal light spectrum our eyes are exposed to," Adair explains.
"There are multiple wavelengths and different different colors they correspond with. ... The shorter the wavelength, the brighter it is," says Adair. Blue light is a shorter wavelength, she adds, so it's brighter compared to red or green light, for example.
"That's why screens use a lot of blue light (compared to other wavelengths) to make it very bright and intense," says Adair, adding that this helps with clarity and contrast.
Do blue light glasses block 100% of blue light?
“No, most of them are not going to block it 100%, but you’re getting a reduction in blue light exposure," says Adair. A better way to think of the glasses is that they filter some of the blue light coming from digital devices, she adds.
Many of the glasses that claim to block higher amounts of blue light may have a yellow, orange or amber tint, Adair says, but the glasses also come in clear varieties.
It's important to note that there are sources of blue light in daily life other than screens — namely the sun, says Adair. Sunlight is actually the largest source of blue light, and screens emit a small amount in comparison, the experts note.
"Daylight is a mixture of all the different wavelengths of light together, which to us looks white," Dr. Craig See, an ophthalmologist from Cleveland Clinic’s Cole Eye Institute, tells TODAY.com. “You’re going to get way more blue light from daylight than you’re going to get from a screen.”
Blue light is also emitted from fluorescent lights, LED light bulbs and televisions.
Although blue light glasses are marketed for use during screen time, people are exposed to blue light around the house and every time they step outside the door, the experts note.
Do blue light glasses work?
Yes, blue light glasses work to reduce exposure to blue light, but no, they don't work to protect your eye health or accomplish many of the other claims sellers make, says See.
"It’s not hard to make a filter that blocks blue light," he explains, adding that there's no robust scientific evidence that blue light glasses are effective reducing eye strain, preventing eye fatigue or generally protecting the eyes.
“Studies haven’t found a big difference between the blue light-blocking glasses and not wearing the glasses,” he says.
That could be because, for many people, the symptoms associated with prolonged screen use aren't caused by blue light, says Adair.
“When you stare at your digital device, two things happen: You don’t blink as much, and your eyes must focus harder,” says Maturi. “Blinking less leaves eyes dry and itchy, while focusing too hard causes headaches, fatigue and blurred vision.”
Many of these symptoms are temporary and will lessen after you stop using the device, Maturi adds.
Another popular claim is that blue light glasses can improve sleep. This is because blue light can suppress the body’s production of melatonin, the sleep hormone, but how much blue light affects melatonin is unclear, Adair says. Also, there haven’t been enough studies demonstrating the beneficial effect of blue light glasses on sleep that apply to the general population, NBC News reported.
Is blue light harmful?
“There is currently no evidence that blue light or screens are causing any irreversible, permanent damage, which is why the American Academy of Ophthalmology does not recommend any special eyewear for computer use," says Maturi.
Adair adds: "Some people may feel a little bit more sensitive to blue light from our screens and monitors. ... (But) the reality is blue light is healthy and safe, and it is not going to harm our eyes.”
At the end of the workday, when your eyes feel strained or blurry, “it’s probably not the blue light as much as it is the fact that you’ve been staring at a static distance, reading, concentrating and experiencing some degree of stress for hours on end,” says Adair.
There is mounting evidence that blue light appears to affect the body’s circadian rhythm, or our natural wake-sleep cycle, says Maturi. But that isn't necessarily a bad thing. During the day, blue light helps wake us up and keep us alert, Maturi notes.
On the flip side, too much blue light exposure from screen use late at night can make it harder to fall asleep, says Maturi. However, studies haven't shown that blue light glasses make a big difference. So, your first line of defense against blue light at night should be reducing screen time before bedtime as opposed to adding blue light-blocking glasses to your bedtime routine, the experts note.
Is there any benefit to blue light glasses?
Some blue light glasses may help filter out some artificial blue light, but no, there's no real benefit to wearing them, says Adair. “You’re not getting any extra protection or health benefits because the blue light wasn’t harming you to begin with,” she adds.
If you love your blue light glasses and feel they make a difference, there’s no reason to stop using them, the experts note. “There isn’t any harm in wearing the glasses or trying them out,” See adds.
However, they could harm your wallet — blue light-blocking glasses or lens filters can cost up to $100 or more.
“Don’t beat yourself up if you want to get the glasses, but they should not be a major expense because they’re not going to do very much for you,” says Adair.
If you’re looking for a fast and low-cost way to reduce your exposure to blue light from screens, the experts recommend trying a blue light filter app or night mode settings on your device.
How can I protect my eyes from my computer screen?
“The No. 1 thing is having a routine eye exam and a full eye assessment — not only for glasses or prescriptions, but also the health of the eyes,” says Adair. This can help figure out whether any eye symptoms are related to one's vision being uncorrected or under-corrected, or an eye condition.
Generally speaking, healthy adults should get eye exams every two to three years, says Adair.
There are some ways to protect the eyes from strain or other symptoms associated with prolonged screen use:
- The 20-20-20 rule: "Every 20 minutes, look into the distance about 20 feet away or leave your desk for about 20 seconds," says Maturi, adding that this can increase your blink rate and move your focal point away from your screen.
- Try to limit screen time 2 to 3 hours before bedtime and use nighttime settings that minimize blue light exposure, Maturi adds.
- Reduce the glare from screens by using a matte screen filter over your computer screen, says Maturi.
- Use artificial tears or lubricating drops to keep the eyes moisturized, says Adair. (Skip the anti-redness drops, says Maturi, which can mask the issue and lead to further discomfort.)
If you wear glasses, Adair recommends adding anti-reflective coating to your lenses instead of blue light-blocking filters. "It'll help to reduce how intense and how bright the light is ... and make your eyes more visually comfortable," says Adair.