The ManicaPost
PEOPLE are increasingly concerned that bright light – especially “blue light” from computer screens – is causing harm, making it a potentially dangerous public health issue.
Eyewear and screen protector companies have started to sell products they say can protect people from these harms.
We do know that blue light at night can interfere with sleep, causing a host of negative effects. But the evidence that the amount of light screens expose us to during the day is harmful is not really there.
Many experts think these products are unnecessary and could perhaps do more harm than good. Still, there’s still a lot we don’t know.
Many of us spend our days staring into bright screens.
Light can cause damage under certain conditions and some studies indicate that the most harmful part of the visible spectrum is blue light, which electronic devices emit to stay visible under bright conditions. Because of that, eyewear companies and screen protector manufacturers have started to market and sell devices designed to protect vision by blocking blue light.
But a closer look at the data reveals that these devices, as appealing as they sound, may not be the solution they’re made out to be.
In recent years, interest in blue blocking lenses has surged. Glasses companies that have long sold eyewear targeted at computer users like Gunnar Optiks have put blue-blocking information on the front page of their websites, newer glasses companies like Felix Gray, have sprung up to meet the seeming demand, The New York Times has written about the question of whether or not blue-blockers could help certain people, and Consumer Reports has put blue-blocking lenses to the test.
There are basically three elements to the pro-blocking blue light argument. First, proponents say doing so will help people sleep easier at night. Second, they say it will reduce digital eye strain.
And third (and most significant, if the claim were true), they say blocking blue light may be necessary to prevent permanent damage to the eye that could result in disease. These diseases include macular degeneration, which causes people to lose some or at times eventually all of their central vision due to damage to the macula, in the center of the retina. (It’s worth noting that these glasses aren’t marketed as medical devices, so their claims are not regulated by the FDA.)
The idea that looking at screens causes permanent damage is a big claim, one that should be backed up by evidence in the form of scientific studies. But studies showing that screens cause this kind of harm do not exist.
It’s not that light or blue light specifically is harmless, it certainly can be. But for now, there is no research showing that these devices expose us to enough light to cause any damage. Doctors do have explanations for why our eyes feel tired and stressed after looking at screens, but those explanations don’t necessarily include light at all.
“People are very worried that we’re looking at our screens more than we ever did,” says Dr Rahual Khurana, clinical spokesperson for the American Academy of Ophthalmologists. “Everyone is very concerned that it may be causing damage to the eye, and it’s a valid concern, but there’s no evidence it may be causing any irreversible damage.”
The research that companies selling blue-blocking products cite falls into three categories: animal studies, in vitro studies of retinal cells exposed to light, and studies of people exposed to outdoor light.
The first two sorts of studies there can give us reason to ask questions about how safe our devices are and to further research that topic, but they don’t show harm. And studies of the sun are interesting, but being exposed to the sun outdoors and working in an office during the day are two drastically different environments.
Shining bright or blue lights into animal eyes can cause damage or changes that we’d associate with macular degeneration, but these experiments are pretty different than looking at your office computer or phone — and the eyes of mice, rats, and even monkeys are more vulnerable than those of people.
In the same way, we can shine lights on human and animal retina cells in a lab and cause similar damage. But again, this doesn’t replicate the way we’re exposed to light in the real world.
“I think it’s largely hype, not science,” says Dr. Richard Rosen, Director of Retina Services at New York Eye and Ear Infirmary of Mount Sinai and Ophthalmology Research Director at Icahn School of Medicine. “They want to sell it; they know people get uncomfortable staring at screens all day, so they say, it’s because of this [blue light issue].”
“I don’t think that anybody has shown screens are causing harm,” says Rosen.
The research that companies selling blue-blocking products cite falls into three categories: animal studies, in vitro studies of retinal cells exposed to light, and studies of people exposed to outdoor light.
The first two sorts of studies there can give us reason to ask questions about how safe our devices are and to further research that topic, but they don’t show harm.
And studies of the sun are interesting, but being exposed to the sun outdoors and working in an office during the day are two drastically different environments.
Shining bright or blue lights into animal eyes can cause damage or changes that we’d associate with macular degeneration, but these experiments are pretty different than looking at your office computer or phone – and the eyes of mice, rats, and even monkeys are more vulnerable than those of people.
In the same way, we can shine lights on human and animal retina cells in a lab and cause similar damage. But again, this doesn’t replicate the way we’re exposed to light in the real world.
“I think it’s largely hype, not science,” says Dr. Richard Rosen and Ophthalmology Research Director at Icahn School of Medicine.
“They want to sell it; they know people get uncomfortable staring at screens all day, so they say, it’s because of this [blue light issue].”
“I don’t think that anybody has shown screens are causing harm,” says Rosen.
David Roger, co-founder and CEO of eyewear company Felix Gray, one of the companies that makes blue-blocking glasses, told Business Insider via email that there are “more and more studies on blue light’s effects on macular degeneration.”
Here’s the issue: while there are studies like those mentioned above and studies about the effects of sunlight, there aren’t studies that show computers or phones are exposing us to a dangerous amount of light.
Rates of macular degeneration are on the rise, according to the National Eye Institute (NEI), but the NEI attributes that to the fact that the population is getting older.
The NEI still lists the primary factors that increase risk for macular degeneration as smoking, race, family history and genetics, and diet — not computer use.
But it’s not just the aforementioned cell or animal data that indicates blue light might be risky, says Dr. Adam Berger, a retina surgeon at the Center for Retina and Macular Disease, who Roger put me in touch with when I explained that the doctors I’d contacted told me they didn’t think blue light was increasing disease rates.
Berger acknowledges that studies about computer use specifically don’t exist, but his argument is a precautionary one — he thinks it’s fair to extrapolate from other studies to say we should protect against blue light, even if it’s hard to measure exactly how harmful computer use is compared to general day-to-day living in the pre-screen era.
Berger is not the only one. There are other doctors, some connected to the Vision Council, a trade group that represents the eyewear industry, that say they find that evidence convincing.
Those groups often point to studies that show that people who have spent a lot of time in the sun have an increased risk for macular degeneration. That’s especially true for light-skinned people who typically have a higher risk in the first place.
White light, including that from the sun, includes blue light, and researchers have attributed the elevated risk of macular degeneration from sunlight to the blue elements of that spectrum.
“Everything we know is that cumulative exposure to light in general increases the risk of macular degeneration,” says Berger. He says that it’ll be difficult to measure exactly how much computer use affects the eye, but that he wears glasses by Blutech to block light in his day-to-day because he thinks “it makes sense to try to mitigate those effects.”
That’s the basic rationale the glasses companies offer too.
“Similar to reducing the amount of sun damage created by wearing sunglasses, wearing amber lenses also filters this harmful blue light from the eyes and prevents the long-term damage high frequency light can cause,” Scott Sorensen, president of Gunnar Optiks, tells Business Insider via email.
But other doctors disagree with the idea of taking preemptive action against something when we don’t know it’s harmful – a new step may do more harm than good.
Khurana says it doesn’t make sense to start recommending treatments, behavioral changes, or purchasing products when there still isn’t proof that they’re solving a real problem.
“If we start jumping from the lab to making policy or to making recommendations, that’s something we have to be careful of.” – Business Insider.
