Blue light glasses may not actually be doing that much good for your eyes, a new study finds.
Blue light glasses have become increasingly popular in recent years, and have been touted to protect eyes against the blue light emitted from computer screens, smartphones, and more. However, a new analysis of 17 randomized controlled trials indicates that this seemingly protective eyewear may not be as beneficial as once hoped.
The new research, which was published in the Cochrane Database of Systematic Reviews journal, indicates that glasses marketed to filter out blue light probably do not reduce eye strain or improve sleep quality.
“There is low-certainty evidence suggesting there may be no advantage with using blue light-filtering spectacle lenses to reduce eye strain compared to standard lenses that don’t filter blue light,” Laura Downie, BOptom, PhD, FACO, FAAO, the lead researcher and an associate professor in the Department of Optometry and Vision Sciences at the University of Melbourne told Health.
“This conclusion is based on consistent findings from three clinical trials that studied effects on eye strain over time periods ranging from two hours to five days,” she said.
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Downie and her team brought together and evaluated relevant clinical evidence, to clarify whether wearing blue light-filtering lenses has any benefits over clear, non-blue-light-filtering lenses.
“In terms of the proposed rationale for blue light-filtering lenses, blue light emitted from computer screens has been suggested as a possible cause of eye strain,” Downie said. “However, this remains contentious.”
Downie explained that the amount of blue light emitted from modern lighting sources—like computer screens—falls well within safe levels and does not pose a significant risk to eye health.
“There is a lack of clear supporting evidence, as well as no compelling biological mechanism through which blue light might cause eye strain directly,” she said.
Downie also noted that it is uncertain whether wearing blue-light filtering lenses before bedtime can improve sleep quality. “[And] no conclusions could be drawn about the possible effects of blue light-filtering lenses on several vision and eye health measures.”
She noted that none of the studies in the review investigated the effects of blue light glasses on the following:
The researchers reviewed studies that ranged in size and length and included more than 600 participants. More research with longer follow-ups in more diverse populations is needed, according to the study authors.
“Our understanding of the safety and efficacy of interventions, such as blue light-filtering lenses, [will evolve] as more research is conducted,” Downie said. “It will be important to review the evidence again in a few years to see if this new research alters our current understanding.”
According to Downie, blue light is part of the visible light spectrum with relatively shorter wavelengths and higher energy than other visible light.
“Sunlight is the main natural source of blue light,” she said. “Artificial light sources also give out varying amounts of blue light, although this is a lot lower than from sunlight.”
She explained that in the modern world, people are often exposed to artificial light, from sources like LED bulbs, computer screens, and other digital devices.
For this reason, the potential effects of blue light on our eyes have stirred both concern and curiosity, especially when it comes to retinal damage, said Inna Lazar, OD, a Connecticut-based optometrist with Greenwich Eye Care.
However, the scientific community has yet to reach a consensus that the blue light from screens can actually cause retinal damage in humans.
The American Academy of Ophthalmology states that there is no scientific evidence that blue light from electronic devices actually damages your eyes.
Yet, the American Macular Degeneration Foundation has suggested that both UV light and blue light may play a role in retinal damage and increase your risk of age-related macular degeneration.
“The conversation around blue light’s potential harm extends to specific situations like staring directly at the sun or other high-intensity sources without proper protection—exposures that are clearly damaging but not analogous to everyday screen use,” Lazar said.
She pointed out that taking regular breaks from screens can relieve the more immediate concern associated with blue light—dry eyes.
It also should be noted that blue light can influence alertness, mood, hormone production, and sleep cycles, Lazar said.
“Exposure to blue light, especially before bedtime, can suppress melatonin production, a hormone crucial for sleep, leading to difficulty falling asleep.”
She explained that by interfering with the body’s natural circadian rhythm, blue light may delay sleep onset as well as reduce overall sleep quality.
That said, Lazar isn’t sure blue light actually causes serious, irreversible damage to eye health.
“While the long-term impacts of blue light on our eye health continue to be a subject of ongoing research, the current understanding leans toward the idea that typical digital device use is unlikely to cause serious harm to our eyes,” she said.
Because of the amount of blue light exposure we experience on a daily basis, people began to speculate on how this exposure could impact eye health, as well as general health and well-being.
But, Downie explained that concerns about the potential for blue light to pose a hazard to the eye are largely based on results from animal studies and cell culture experiments in the laboratory that reported that high-intensity, short-wavelength visible light exposure can induce retinal phototoxicity.
“However, a direct link to environmental blue light exposure and retinal phototoxicity in humans is currently unproven,” Downie said, “and whether findings from animal and benchtop lab studies are transferable to humans remains questionable.”
That said, marketing teams still seized on the increasing worries about how blue light might affect our eyes and sleep, resulting in a spike in people wanting these products, said Lazar. “Anecdotal evidence, beliefs about blue light’s negative effects, and some doctors recommending them just to be on the safe side, further fueled [blue light glasses’] popularity.”
Lazar says the biggest issue of prolonged screen use is that it can cause dry eye symptoms and dry eye disease due to the lack of blinking.
“It’s important to remember to take frequent breaks when on the screen, match the brightness of the screen to the brightness of the room, and also make sure the screen is located slightly below the eye line and not above,” she said. “[And] never skip the sunglasses.”
As for those blue light glasses sitting on the desk in your office or perched on top of your head, you don’t have to get rid of them, especially if you enjoy wearing them.
“I have patients who work on the computer late at night and report improved sleep when they wear their blue light-blocking glasses,” Lazar said. “Also, they do look pretty cool if you’re into trends.”
That said, if you are experiencing eye strain, do not simply rely on blue light glasses to alleviate your symptoms. Instead, see an optometrist for a thorough assessment of the health of your eyes, and how your vision is functioning.
Underlying eye conditions such as vision issues and dry eye disease can be associated with eye strain, Downie said. In the meantime, try not to worry too much about blue light.
“If you find that blue light-blocking glasses help you, then keep on wearing them; if not, then don’t worry about it,” Lazar said. “You can always adjust your screen at night to remove the blue light if you don’t feel like investing in a pair.”
