Did you know that many people around the world spend more time each day looking at screens than they do sleeping? According to data from 2016, the average US digital device user spends 444 minutes (or just under seven and a half hours) in front of a screen each day; in China, this figure is 480 minutes, and in the UK, it’s 411 minutes. The same data shows that, given the increasing prevalence of smartphones and tablets, mobile devices account for nearly half of all screen time, with televisions and laptops making up the remainder.
In the face of all this screen time, many health experts are concerned about the toll our smartphone fixation in particular may be taking on our vision. Numerous studies in recent years have linked heavy smartphone use with a range of eye problems, including:
Computer vision syndrome (digital eye strain)
Also known as digital eye strain, computer vision syndrome (CVS) is an umbrella term for a set of connected symptoms that can result from two or more hours of looking intensely at a screen. Interestingly, CVS is similar to repetitive motion injuries like carpal tunnel syndrome, except that instead of affecting larger muscles like those of your hands and wrists, it affects the muscles of your eyes. This happens because, when you’re looking at a screen, your eyes are continually focusing, refocusing, and reacting to changing images and text on the screen. All these actions require considerable effort on the part of your eye muscles.
Add this strain to the fact that you blink less and thus refresh your eyes less often when you’re looking at a screen, and it’s not surprising that CVS symptoms start to appear after a couple of hours. If you work on a computer or like to spend long periods of time on your phone, you’ve probably experienced some of these symptoms yourself: they include eye strain and fatigue, blurred or double vision, dry and itchy eyes, and tight facial, neck, and shoulder muscles.
Dry-eye disease
Dry eyes are not only a symptom of CVS; they’re also a vision problem in their own right. In order for your eyes to stay healthy and comfortable and to see well, it’s essential to have a consistent, adequate layer of tears on the surface of the eye. However, with dry-eye disease, the eyes do not produce enough tears, which causes them to become red, itchy, and irritated. Other symptoms of dry-eye disease include sore or fatigued eyes, blurred vision, and what’s known as a foreign body sensation, which is the feeling that something like grit or debris is in your eye. Over time, dry-eye disease can result in significant inflammation and even cause scarring to the front surface of the eye. The condition is most commonly found in older adults, but the prevalence of dry-eye disease in young people is on the rise, particularly among children who spend more time on their phones.
Macular degeneration
A study from the University of Toledo that was published in 2018 in the journal Scientific Reports has revealed that the blue light emitted by smartphones and other digital screens may increase your risk of macular degeneration. In this condition, which is one of the leading causes of blindness worldwide, the central area of the retina known as the macula deteriorates or becomes damaged. This causes dim or blurred central vision, which can impact everyday tasks like reading or driving and can eventually lead to severely deteriorated sight and eventual blindness. The University of Toledo study found that shining blue light, like that emitted by a smartphone, on eye cells transformed retinal molecules into a kind of poison that is toxic to the photoreceptor cells the retina relies on to sense light and, consequently, to see.
How you can protect yourself
While these eye health problems are certainly serious and could lead to long-term damage if ignored, the good news is that there are many things you can do to protect yourself and preserve your eye health. Obviously, for most of us, it’s not possible (or desirable) to eliminate screen time altogether. However, following the simple tips below can go a long way toward mitigating smartphone-related eye issues.
Blink—Because we unconsciously blink less often when looking at screens, doing some deliberate, conscious blinking exercises can help keep your eyes moist and refreshed. Experts recommend the following: every 20 minutes, blink slowly 10 times, fully closing your eyes each time and waiting a moment before you open them again.
Avoid smartphone use at night—Eye strain sets in more quickly if your device’s screen is brighter than the ambient light in the room. To make your screen time easier on your eyes, use your smartphone in a room with good, bright lighting and avoid smartphone use at night or in the dark. Doing so will also help prevent the sleep disruption that can be caused by using your smartphone before bedtime.
Take breaks—Taking regular breaks from your screen is one of the most important things you can do to relieve eye strain and protect your eyes from damage. Ideally, you should take a 15-minute break after every two hours of screen time to give your eyes a chance to properly relax.