Many of us spend large chunks of our lives staring at computer screens, smartphones and tablets. Long periods of screen time can cause headaches, eyestrain and blurred vision – all symptoms of a condition that’s been termed ‘computer vision syndrome’. This is caused by our eyes having to constantly work to keep focused over the short distance to the screen. We also blink three times less frequently when using a screen – just 5 times a minute – which makes our eyes dry and itchy.
However, studies have so far failed to find any link between screen use and long-term eye health conditions, such as short-sightedness or cataracts. One 20-year study at the Ohio State University found that children who spent long periods in front of a computer screen or television were not any more likely to need glasses later in life.
However, spending at least 14 hours a week playing outside has been shown to reduce the chances of becoming shortsighted later. This may be because brighter outdoor light levels stimulate the release of dopamine, which slows the growth of the eyeball and makes it less likely to become distorted later in life.
Once you reach adulthood, the best you can do to reduce eye fatigue is take a break from the screen every 20 minutes to gaze out of the window for 20 seconds.