Heavy screen users often buy blue light-filtering eyeglasses to protect their eyes -- but they may be wasting their money, a new study suggests.
A new research review suggests these blue light-filtering glasses probably make no difference to eye strain, eye health or sleep quality, at least in the short term.
And it's still unclear whether these glasses protect against retina damage because the research did not evaluate this, according to findings published in the Cochrane Database of Systematic Reviews.
"We found there may be no short-term advantages with using blue light-filtering spectacle lenses to reduce visual fatigue associated with computer use, compared to non-blue light-filtering lenses. It is also currently unclear whether these lenses affect vision quality or sleep-related outcomes, and no conclusions could be drawn about any potential effects on retinal health in the longer term,"said senior author Laura Downie. She heads the Downie Laboratory at the University of Melbourne in Victoria, Australia.
"People should be aware of these findings when deciding whether to purchase these spectacles,"Downie added in a Cochrane news release.
Researchers reviewed 17 randomized controlled trials from six countries. The studies' size ranged from just five participants to 156. Study length varied from one day to five weeks.
The quality and duration of the studies need to be considered, Downie said.
"We performed the systematic review to Cochrane methodological standards to ensure the findings are robust. However, our certainty in the reported findings should be interpreted in the context of the quality of the available evidence. The short follow-up period also affected our ability to consider potential longer-term outcomes,"Downie noted.
High-quality, large clinical research studies with longer follow-up in more diverse populations are still needed to more clearly determine potential effects of blue light-filtering glasses on visual performance, sleep and eye health, said co-author Sumeer Singh, a postdoctoral research fellow in the Downie Laboratory.
"They should examine whether efficacy and safety outcomes vary between different groups of people and using different types of lenses,"Singh said in the release.
Although their effectiveness remains in question, any side effects of the glasses tended to be mild, infrequent and temporary. Among them were lower mood, headaches and discomfort wearing the glasses.
"Over the past few years, there has been substantial debate about whether blue light-filtering spectacle lenses have merit in ophthalmic practice. Research has shown that these lenses are frequently prescribed to patients in many parts of the world, and a range of marketing claims exist about their potential benefits, including that they may reduce eye strain associated with digital device use, improve sleep quality and protect the retina from light-induced damage,"Downie said.
"The outcomes of our review, based on the current, best available evidence, show that the evidence is inconclusive and uncertain for these claims," she continued. "Our findings do not support the prescription of blue light-filtering lenses to the general population."
More information
The Sleep Foundation has more on blue light.
SOURCE: Cochrane, news release, Aug. 17, 2023