We all know the feeling. Realising you’ve been staring so intensely at a screen that you suddenly blink back to reality, dazed and confused, with an overwhelming urge to give your sore eyes a big ol’ rub. They feel dry and irritated, and - come to think of it - you’ve got a bit of a headache too.
Symptoms like these have become increasingly common in recent years, largely due to the amount of time we spend in front of screens. It makes sense; many of us work in an office setting, meaning we’re gazing at a laptop or computer for roughly eight hours a day. Factor in time at home or on the bus scrolling through newsfeeds and messaging friends, and you really start to rack up a big number. For lots of us, excessive screen time takes its toll, resulting in what’s known as Digital Eye Strain, or DES. Symptoms include those mentioned above; dry eyes, headaches, fatigue (but to add insult to injury, difficulty sleeping), irritability… the list goes on. It’s incredibly common; this 2018 study suggests it may affect more than 50% of computer users worldwide, while this piece of research describes it as “an emerging public health issue”. But what is it about screen time that actually leads to DES’ particular set of nasties?
You might not think something so small could have such a huge effect, but bad lighting is a key culprit when it comes to DES. If you’re lucky enough to be based in a fancy-pants office, chances are they’ve optimised lighting to ensure the space is adequately lit. That said, these days many offices opt for fluorescent lighting over traditional incandescent bulbs, as it’s a more energy-efficient option. Unfortunately though, this harsher light source has been shown to increase headaches among office workers. Those of us working from home or in a more makeshift environment may face different lighting challenges. If lighting is too dim (from a lamp or low wattage bulb) or too bright (causing a glare on your screen) you’re more than likely putting your eyes under extra pressure as you work.
Another cause of DES is a poor seating position or laptop arrangement. Again, anyone working from home or at a makeshift desk may relate to this one. Having to look up at your computer if it’s too high, or down at your laptop if say, you’re sitting on the couch, will put an extra strain on both your neck and eyes. Similarly, if you’re hunched over your desk with your face right up against the screen, you’re more likely to be full of aches and pains when you finally clock off.
Finally, the blue light emitted by digital devices could also be contributing to your DES symptoms. Blue light is naturally produced by the sun, but an artificial version is emitted by phones, tablets, TVs and computers. Our absorption of it is linked to our circadian rhythm; meaning that as the sun sets, we naturally start to feel sleepy. Since we’re absorbing way more blue light than previous generations, it stands to reason that too much of it could be interrupting our bodies’ natural clocks. Researchers from the Harvard Medical School conducted (what sounds like a horrendous) trial on migraine sufferers. When exposed to artificial blue light in a clinical setting, it was found that their aching heads got even more painful, further suggesting a link between excessive exposure to blue light and DES.