In 2020, the COVID-19 pandemic forced many in-person activities into virtual settings, spurring new product trends. Blue light glasses became popular as screen time increased. These glasses are meant to block blue light, the type emitted by electronic devices, in order to lessen potential eye damage and strain from staring at screens.
One of the main issues related to screening time most common in society is digital eye strain (DES). DES is linked to a variety of symptoms, including back, neck and shoulder pain, headaches, eye discomfort, vision issues, fatigue and eye irritation.
“DES, also known as computer vision syndrome, encompasses a range of ocular and visual symptoms, and estimates suggest its prevalence maybe 50% or more among computer users,” said Amy Sheppard and James Wolffsohn in a 2018 study published in BMJ Open Ophthalmology. “Symptoms fall into two main categories: those linked to accommodative or binocular vision stress, and external symptoms linked to dry eye. Although symptoms are typically transient, they may be frequent and persistent, and have an economic impact when vocational computer users are affected.”
Hannah Bergman, sophomore finance major, uses blue light glasses because she suffers from headaches after long periods of looking at a screen, a characteristic symptom of DES.
“I tend to get headaches by the end of the school day from using computers all day in class and working on homework,” Bergman said. “My boyfriend also experiences the same thing and he loves wearing the blue light glasses.”
Although many people attest to the ability of blue light glasses to lessen the symptoms of DES, the American Academy of Ophthalmology does not endorse the use of blue light glasses due to an absence of scientific support that blue light causes damage.
Dr. Stephen Runyan, associate professor of biology, said that blue light glasses do work in that they filter out the short blue wavelength on the visible light spectrum. Therefore, they do what they advertise. However, science has not yet determined that the level of blue light humans consume through screens can truly damage the eyes.
“If I go back to my experience in the pharmaceutical industry, one of the models that was used in testing certain medications in the eye was the blue light model,” Runyan said. “They would use rodents and they would expose them to high-intensity blue light that did cause retinal damage, but it is certainly more extreme than any blue light we would be exposed to from our screens or from the sun. In that model, blue light damaged the retina, and drugs like antioxidants were helpful in preventing that because the damage is due to free oxygen radicals, and antioxidants could prevent the damage from the blue light. Could blue light glasses potentially protect in a scenario like that? Maybe. That would be an interesting study to do.”
Currently, Runyan said it is difficult to prove that blue light glasses are beneficial. He also said there does not appear to be a clear connection between blue light and DES, meaning that blue light glasses do not directly relieve the symptoms of DES.
“My understanding with eye strain would be that your muscles are being overactive, probably primarily due to the close vision, which would require the contraction of your muscles for close vision,” Runyan said. “I don’t think that blocking blue light would have an impact on the closeness of your vision. Your eyes still have to focus. The muscles still have to constrict, the ciliary muscle that controls the shape of your lens and also the convergence of your eyes for near vision. Blue light glasses are not going to help and blocking blue light is not going to help your muscles need to contract less or focus on a near object any less, so it could just be the proximity, not the blue light.”
Runyan credits the claim that blue light glasses do help relieve DES symptoms to potential scientific correlations between blue light and DES that have yet to be explored, or to a possible placebo effect around the belief that blue light glasses should relieve such symptoms.
Runyan said one of the challenges with researching the effects of blue light is that it is difficult to construct studies that look into the effects of blue light on humans. These studies will likely require long time spans, as well.
“We don’t know,” Runyan said. “There is nothing to show what the level we are exposed to does. If blue light-blocking glasses can be of some benefit, then there is no harm in wearing them. So if you feel inclined to wear them, if you feel there is protection, you are not being harmed by them in any way. Go ahead and do it. If you opt not to, that’s fine too.”
The American Academy of Ophthalmology said that DES can also result from decreased blinking when staring at a screen.
To avoid DES, the organization suggests remaining 25 inches from a screen, — about arms length — taking frequent breaks from screens and increasing contrast on the screen.