"The groundwork of all happiness is health." - Leigh Hunt

Study questions whether glasses with blue light filters really work

August 18, 2023 – Despite manufacturers' claims, blue light-blocking glasses are unlikely to scale back eye strain for individuals who spend numerous time in front of computer screens or cell phones, a latest study says. The glasses are also unlikely to enhance wearers' sleep habits, in keeping with the study, published this week.

Blue light blocking glasses are typically advertised as with the ability to filter out the possibly harmful effects of blue light from screens, similar to eyestrain, dry eyes and sleep disturbances. Interest in blue light blocking glasses increased in the course of the COVID-19 pandemic as more people stayed home and checked out their computers and phones. They are sometimes prescribed by opticians.

The study was conducted in Cochrane database of systematic reviews The study examined data from 17 clinical trials in six countries on Thursday, involving a complete of 619 people.

“We found that there may be no short-term benefits of using blue light filter lenses to reduce visual fatigue during computer use compared to lenses without blue light filter,” said lead creator Laura Downie, PhD, an associate Professor of Optometry and Vision Sciences on the University of Melbourne in Victoria, Australia, said in a Opinion.

“It is also currently unclear whether these lenses affect vision quality or sleep-related outcomes, and no conclusions have been drawn about potential long-term effects on retinal health. People should be aware of these findings when deciding to purchase these glasses.”

Researchers have found that one reason the glasses don't assistance is because the quantity of blue light absorbed from computer screens and other artificial sources is just about one-thousandth of what people get from natural daylight. In addition, blue light glasses typically only filter out about 10 to 25 percent of blue light.

“Our results do not support the prescription of blue light filtering lenses to the general population,” Downie said.

Eye experts say you may reduce eye strain by simply reducing the period of time you spend in front of a screen or by taking regular breaks. To improve sleep, avoid watching a screen for just a few hours before bed.

The researchers noted that their evaluation had limitations. None of the studies examined contrast sensitivity, color discrimination, glare, macular health, serum melatonin levels, or patients' overall vision satisfaction.

The duration of the various studies also varied. Further studies on the usage of glasses with blue light filters are needed, the researchers said.