The Misconceptions About Blue-Light Glasses: A Comprehensive Study

• Research

Blue-light filtering glasses have been touted as a solution to the eyestrain associated with prolonged computer use. However, a recent review suggests that these glasses may not be as effective as they are often portrayed. The study, led by Laura Downie, an associate professor of optometry and vision sciences at the University of Melbourne, examined 17 randomized controlled trials and found that the popular glasses may not significantly reduce eyestrain or improve sleep quality and retinal health.

Companies such as Warby Parker and Felix Gray, among others, market these glasses as potential aids to alleviate conditions such as eye fatigue, dry eyes, and eyestrain. However, the research paints a different picture. As some companies claim, eyestrain is not caused by blue light but rather by prolonged screen exposure. The human eye naturally blinks around 15 times a minute, but this rate decreases to about five to seven times when we are focused on screens, resulting in dry eyes and potential eyestrain.

"The truth about blue-light glasses: an in-depth look into the science and the misconceptions."

Do Blue-Light Glasses Help?

The review evaluated three trials that considered the effect of blue-light-reflecting lenses and eyestrain. These trials, involving 166 participants, found no significant difference in visual fatigue between those wearing blue-light filtering lenses and those not wearing such lenses. Kevin M. Miller, a professor of clinical ophthalmology at the University of California at Los Angeles, said these findings were expected, suggesting that consumers might want to rethink purchasing blue-light-blocking lenses.

What About Sleep Quality?

The circadian rhythm, our internal clock that regulates sleep, among other things, can be affected by light and darkness. Blue light is absorbed by photoreceptive cells in the retina that significantly impact our biological clock. The suppression of the hormone melatonin, which signals darkness, can also be affected by this light. Consequently, the idea behind blue-blocking lenses is to prevent this light from entering the eye and disrupting the circadian rhythm. However, the review found inconsistent findings on the effect of these glasses on sleep quality.

Other Effects of Blue-Light Lenses

The review also found little or no effect of blue-light filtering lenses on visual performance and daytime alertness. The researchers attempted to examine the impact of these lenses on contrast sensitivity, color vision, and "discomfort glare," a phenomenon where bright light sources cause eye discomfort. However, none of the studies reported these outcomes, so it was impossible to conclude possible effects.

Possible Remedies for Eyestrain

Instead of investing in blue-light glasses, consider using the "20-20" rule: every 20 minutes of screen time, look at an object 20 feet away for 20 seconds. Sitting an arm's length from the computer screen and using glasses with the correct prescription can also help reduce eyestrain. If eyestrain persists, seeing an eye-care health professional for a thorough examination is recommended.