Blue light glasses have been a buzzy eyewear item for years. The glasses are designed to filter out blue light — which is typically emitted from screens — and many fans claim they can reduce the risk of eye strain and migraines. Some say these glasses may improve your sleep.
But for all the hype surrounding them, blue light glasses have been controversial, with many doctors arguing that they don’t live up to the claims. Now there’s a new study that suggests these glasses don’t do much of anything. Here’s what you need to know.
What does the study say
The study found that when compared to regular lenses, blue light glasses did not help visual performance, protect the eyes, or enhance sleep quality.
What are the main findings?
The study published in Cochrane Database of Systematic Reviewsanalyzed data from 17 randomized controlled trials in which blue light filtering lenses were compared with blue light filtering lenses in adults. Sample sizes for each trial ranged from five to 156 participants, with follow-up periods ranging from less than a day to five weeks.
The researchers analyzed data for factors such as visual performance, visual fatigue, eyestrain, and sleep quality and found that blue light glasses didn’t do much. The researchers also found that the bulk of the studies had a high risk of bias (eg, there were flaws in the design or analysis, and that the results might not be accurate).
The conclusion of the study broke everything. “This systematic review found that blue-light-filtering eyeglass lenses may not relieve symptoms of computerized eye strain, over a short-term follow-up period, compared to non-blue-light-filtering lenses,” the researchers write. “Based on the best evidence currently available, there is likely to be little or no effect of blue-light-filtering lenses on better-corrected visual acuity (the ability to see shapes and details at a distance) compared to non-blue-light-filtering lenses.”
The researchers noted that potential effects on sleep quality were “undetermined” and that there was “no evidence” to support other claims surrounding blue light glasses, including that they help reduce glare, improve eye health, affect melatonin levels, or help people see better.
Basically, there has been no data to suggest that blue light glasses are effective.
“The prescription of blue light-filtering eyeglass lenses began to gain popularity in the 2000s, based on the suggestion that these lenses might protect the eyes from any potentially harmful effects of blue light,” said a study co-author. Laura Downey, Associate Professor in the Department of Optometry and Vision Sciences at the University of Melbourne, tells Yahoo Life. However, whether blue light emitted from computer screens causes eye strain remains controversial.
What the experts think
doctor. Vivian ChibayamaM.D., an optometrist at UCLA Health, told Yahoo Life she wasn’t surprised by the results. “There is no evidence that they help,” she says.
Philip Yohas, an assistant professor in the Ohio State University College of Optometry, told Yahoo Life that he, too, wasn’t shocked by the conclusion. “Everything so far in the literature points to weak evidence — at best — that blue-light glasses do anything,” he says. “Most studies report almost no effect.”
Dr. Mina Massaro Giordano, co-director of the Penn Dry Eye and Ocular Surface Center and clinical professor of ophthalmology at the University of Pennsylvania. “There hasn’t been a great science out there with blue light blocking,” Massaro Giordano told Yahoo Life. “We as ophthalmologists don’t say, ‘You should get blue-light-blocking glasses.'” “
The idea of blue-light glasses isn’t entirely out of left field, Downey says. She says, “It is important to realize that blue light can regulate normal physiological functions, such as the circadian rhythm. However, concerns have also been raised about the possibility that blue light may pose an eye hazard. This is largely based on the results of animal studies, and in vitro cell culture experiments that showed exposure to high-intensity, short-wavelength visible light can damage retinal cells.”
But the direct link between blue light and eye health in humans is “unproven” and suggests that conclusions drawn from these animal studies could apply to people, Downey says.
“The light emitted from modern light sources, including computer screens, is within safe levels, and therefore does not pose any significant risk to eye health,” she says, noting that the largest source of blue light that people are exposed to is natural sunlight.
As for the interest generated by these glasses, Yohas says a lot of it is down to marketing. “Lens companies and practitioners can sell blue light products for a little more,” he says. “There is a financial advantage to increasing the ability of products to blue light.”
why does it matter
Blue light glasses usually cost more than those with regular lenses and you can end up spending more on a product that doesn’t live up to its claims. Shibayama says it “does no harm” (other than to your wallet) to use blue light products, but there are other things you can do to improve your eye health.
“I tell patients to use night mode on their devices, which reduces blue light,” says Shibayama. She says taking breaks from screens by following the 20/20/20 rule (every 20 minutes looking 20 feet away for 20 seconds) can also help with eye strain.
If patients are interested in blue-light glasses, Massaro Giordano says she tells them there likely won’t be any harm from them. “Some people feel less eye strain,” she says. “Could it be a placebo? I don’t know.”
Yuhas says he has told his patients who are interested in blue light glasses that there is “little evidence that they will do anything to help with visual comfort or performance.” He adds, “I tell them that if they like the light yellow color it gives, then God bless them. But they should moderate their expectations.”