It's 2 p.m., and you've been staring at your laptop screen all day. We've all been there: Itchy eyes, blurry vision and all the other symptoms of eye strain are something most of us suffer from, especially those of us in the line of work leading us to read (or write) at TechRepublic.
If you've searched for a solution to your computer eye strain you've probably heard about blue light and its reported contribution to your discomfort. You've probably also seen advertisements or product recommendations for glasses that claim to filter out the blue light emitted by computer screens, reducing risks of macular degeneration and reducing discomfort — is the solution really that simple?
That depends on who you ask, but it doesn't mean the answer is cut-and-dry, especially when it comes to answering the question of whether those over-the-counter glasses will help reduce what's commonly come to be called computer vision syndrome.
Light operates on a spectrum, and different wavelengths produce different colors of light. The blue wavelengths, according to Harvard Health, "are beneficial during daylight hours because they boost attention, reaction times, and mood," and inversely effective at night, as they can throw off the body's natural rhythm by confusing it with light it's only supposed to get during the daytime.
Blue light is also highly energetic, Harvard Health said, containing more energy per photon than any other part of the visible spectrum of light. Because it is more energetic, Harvard said, it's more likely to cause damage to various parts of our body when absorbed.
Now for the eyes: The American Macular Degeneration Foundation says that blue light, and the ultraviolet light that sits near it, but outside the visual range, on the spectrum, "is generally understood to be harmful to the eye, possibly leading to cataracts and other eye diseases such as age-related macular degeneration (AMD)."
The argument for blue light-filtering glasses makes perfect sense, then: We wear sunscreen to protect our skin, so we need to do the same for our eyes, even indoors since we are constantly using screens that emit blue light.
Dr. Howard Crane, a Michigan-based optometrist, said that he's seen enough eye damage in young patients to lead him to say it's not a myth. "Blue light definitely causes harm to the retina, and in particular the macula (the area at the back of the eye where vision is focused). I'm looking in the eyes of people that are on computers a lot, and I'm seeing that there is damage to the macula, and it is definitely from the blue light," Crane said.
The macula, Crane explained, is where the sharpest part of our vision comes from. Older people often suffer from macular degeneration due to aging and long-term sun damage, but Crane said he's seeing it increasingly often in young people. "If you lose your macula you'll end up with serious vision loss that is, at this point, irreversible," Crane said.
Dr. Crane believes that wearing blue light glasses is extremely important. "We're getting blue light constantly from practically everything we use today, and it's damaging my patient's eyes."
The glasses themselves may not be as cut-and-dry a product as that, though. The second of the Harvard Health articles linked above says that LED lights in electronic devices are nowhere near strong enough to do lasting damage. "Consumer electronics are not harmful to the retina because of the amount of light emitted. Recent iPhones have a maximum brightness of around 625 candelas per square meter," Harvard Health said. Many retail stores have ambient illumination twice as great, while the sun is ten times greater than the iPhone, Harvard Heath added.
"Compared to the risk from aging, smoking, cardiovascular disease, high blood pressure, and being overweight, exposure to typical levels of blue light from consumer electronics is negligible in terms of increased risk of macular degeneration or blindness," Harvard Health said.
Typical over-the-counter blue light filtering glasses also only filter out about 20% to 30% of blue light, which Crane said is far too little to be effective. If you're considering blue light glasses from the store, put them back: They're simply not going to do the job, if needed, and Harvard also pointed out that many OTC blue light glasses manufacturers have been fined for making misleading statements.
You may have noticed a distinction between two terms used in this article: Eye damage and computer vision syndrome, the latter of which displays symptoms of eye strain, fatigue and muscle pain instead of macular degeneration.
There is a distinct difference, and it's one that an NPR interview makes clear: There is no mechanism by which blue light causes digital eye strain. It's more likely that you can chalk that up to your bad posture.
Damage to the eyes, on the other hand, is something we know blue light does. It's not enough to buy an over-the-counter pair of filtering glasses either, Crane said, because you can't verify the legitimacy of the claims the manufacturer makes and they usually are too weak.
In addition to getting quality blue light filtering lenses, Dr. Crane also recommends that people perform the standard recommended exercises to reduce eye strain and discomfort, which again is something distinct from macular damage.
Crane suggests the 20-20-20 rule: Every 20 minutes take 20 seconds to stare at something at least 20 feet away. "You can adjust that to the 5-5-5, 10-10-10, or anything else that makes you feel more comfortable," Crane said. He also recommends regular stretching, breaks and good posture, all of which he said can help relieve muscle strain and decrease fatigue.
Eye damage caused by electronic devices may still be up for debate, but ultimately it may simply be a matter of "better safe than sorry" when it comes to irreversible macular degeneration. You may not even need to go out and get a pair of dedicated blue light glasses if you already wear prescription lenses, either: Crane said that many existing pairs have blue light filters in them, as it's a standard part of many glare reducing technology.
If you do decide you need a pair, you won't be doing yourself any harm; just be sure you buy a pair from a trustworthy source.
This article originally appeared on TechRepublic.