For many of us, our lives increasingly involve looking at digital screens — for work and play.
"It is known that people who undertake more intensive or expended periods of computer use — usually considered about four hours a day or more — are more likely to experience eye strain symptoms," Professor Laura Downie, a clinician scientist from the University of Melbourne, said.
"Those types of symptoms can include tired eyes, burning eyes, or just discomfort."
Blue light has been blamed for much of the increase in cases of eye strain, leading many to buy special glasses that claim to combat the problem.
Blue-blocking lenses for prescription glasses have a special coating designed to reduce the amount of blue light passing through the lens, and thus into the eye.
Sumeer Singh, a postdoctoral clinical research fellow at the University of Melbourne, said sales of blue light glasses had boomed — especially at the height of the COVID-19 pandemic.
"Because of the increase in the prevalence of digital eye strain, there has been a lot going around from media advertisements or from the optical industry," he said.
But questions have been raised about how effective they really are.
Singh is part of a team that recently compared standard clear lenses with blue light blockers.
"What we found is that blue light blocking lenses did not reduce eye strain compared to the standard clear lenses," he said.
Downie said the study's results backed up the conclusion of previous international research that came to the same conclusion.
As for whether blue light glasses help people to sleep — the other major purported benefit —she said the jury was still out.
What will help to reduce eye strain?
While wearing blue light glasses don't do any real harm, Downie said there were other effective things people could do to avoid straining their eyes.
"We would recommend that they discuss those symptoms with their eye care professional, such as an optometrist," she said.
"A person might require glasses, and it might actually be that factor that is driving their eye strain.
"Modifying the frequency or duration of digital device use, enhancing the working environment, ensuring the ergonomic setup is suitable; all those factors are important for reducing the likelihood of experiencing visual fatigue with digital devices."
