Because of the widespread use of tech devices, we’re now exposed to more blue light than ever, with a 2020 study published in the Indian Journal Of Ophthalmology finding that during Covid-19 lockdowns, over 32% of the study population used a blue light-emitting device between nine and 11 hours per day.

Various studies have looked into the effects of blue light on our health, including how it impacts the skin, eyes and sleep. For example, a 2014 study published in the Proceedings Of The National Academy Of Sciences Of The United States Of America suggested that when people are exposed to blue light in the evening hours, their bodies don’t release as much melatonin, which could delay and disrupt sleep cycles.

Many people believe that blue light could be damaging our eyesight and health, but the evidence to suggest that idea is limited. A 2019 study on animals found that blue light can damage cells in the retina. However, Roshni Kanabar, optometrist and clinical adviser at the Association of Optometrists, says that this study, and other similar scientific evidence, might not be totally trustworthy: “The time and intensity of exposure to blue light in these studies was far more than that of natural daylight and that of screens, so this cannot be applied to humans.”

However, Dr Perry suggests that, despite the lack of evidence, blue light could be inadvertently impacting our eyesight: “It is well known that sitting in front of the PC leads to 50% less blinking per minute (normal is 15-20 times),” he says. “This can lead to dry and red eyes, which in turn can put more strain on the eyes.”

Do blue light glasses actually work? We asked the experts