The Truth About Blue Light Glasses — Fact vs Fiction
July 22, 2019 7:04 pm
Blue light glasses are all the rage lately. If ever there was an eyewear item that actually achieved the effect of “going viral”, it was these. They are a valuable tool of our computer age. It often seems like unless one’s job is purely mechanical, it is now partly on some kind of digital device.
But what about the science behind blue light glasses?
Now that is where things get complicated….which is why we tried to compile the general findings on the various claims in regards to blocking blue light.
Claim 1: Blocking blue light helps sleep patterns.
Current science says: True. Over 99% scientific consensus.
Why: Humans are wired by our circadian rhythm of darkness and light, activity versus sleep. In nature, the only thing that produces blue light is the sun. Studies have shown for decades that our melatonin production, the hormone mostly responsible for inducing sleep, is highly dependent on when the brain stops sensing blue light. This effect is known by just about anyone that has gone camping for several days; a few nights in and you’re sleepy right after sundown.
How to apply: Wearing blue light blocking glasses, or using programs that do the same, will drastically help your sleep quality. This is especially true for those that do computer work late at night, or who regularly travel into new time zones. Most of all, it is important to monitor blue light with children.
Claim 2: Blocking blue light helps eye strain.
Current science says: Likely true, but always a subjective effect.
Why: What makes blue light unique, as opposed to the rest of the visible light spectrum, is that the front structures of your eye cannot block it. The basic theory behind the eye strain issues is that because of its wavelength, the blue light will focus in front of the retina rather than on it with the rest of the image. This leads to our focusing system, called “accommodation”, will constantly be engaged in attempting in the hopeless attempt to get this blue light focused onto the retina where it belongs.
How to apply: In our experience in hearing back from patients that try blue light lenses for eye strain, a big variable seems to be duration. In general, their effect seems quite minimal for those that use a computer only occasionally. For people that mix in their computer work with intervals of speaking to colleagues, working with their hands, or looking far into the distance, they often report little benefit. For these people, wearing a correct Rx tends to have a much stronger effect. For those that do computer work however as their primary work product, with each day comprising several hours of locked-in screen time, it is rare that they go back after going to blue light blocking lenses.
Claim 3: Blue light is harmful to the retina. Exposure hastens ocular disease such as macular degeneration.
Current science says: Not true. Studies have conclusively shown that actual cellular damage of the retina shows no causal relationship with blue light.
Why: This question has been under intense study for several years, due to its pressing nature. Macular degeneration can be visually devastating. It is the number one cause of legal blindness in developed countries. That said, studies have simply not shown a relationship. In short, it is believed that the retinal cells are quite resilient. What changes in macular degeneration is thought to mostly be a loss of the protective photopigments that are normally found. These decline with age, and there are significant variables such as UV exposure, diet, and genetics. Blue light exposure has not been proven to belong among these contributing factors. Studies are ongoing.
Claim 4: Blue light lenses are all the same.
Current science says: Not true. Lenses vary widely in how much blue light is actually blocked. Some of them on the market have been found to block so little as to be negligible.
Why: Like any market trend, there was a rush for as many retailers as possible to offer blue light blocking lenses. The reality is that the technology involved is complicated. Any credible blue light blocking product will list the percentage that is blocked. If it doesn’t, that is likely all one needs to know. At Tribe Eyeworks, we offer two “grades” of blue blocking lenses. Our standard lens blocks 22%, and is completely clear optically. We also offer a stronger blocking version that stops 52%. We have found that for most applications, anything over about 15% will be noticeable. To get above 40% however, lenses will gain a barely noticeable tint to them. Always know before you buy.