The amount of time people spend looking at screens has grown dramatically, from using computers at work to watching television at home and being glued to a smartphone or tablet most of the day. It is a wonder how little trouble this appears to be causing our eyes.
While smartphone and tablet use has greatly increased the average person’s exposure, says Chris Hammond, ophthalmology professor at King’s College London, “we are not seeing any epidemics of eye problems related to that”.
He does, though, recommend limiting children’s screen use because the phenomenon of pre-school children spending hours on phones and tablets is recent and effects are unknown.
Globally, a 16-45-year old typically spends 418 minutes — two minutes short of seven hours — a day looking at screens, say researchers Millward Brown (see graphic). This comprises watching television, using the internet on a laptop or personal computer and viewing smartphones and tablets.
Smartphones have become the world’s largest screen medium. Combining smartphone minutes with tablet use, mobile devices account for nearly half of all screen time.
In many cases, people may spend longer on screens than they do sleeping. Figures range from 317 minutes in Italy to 540 in Indonesia. The average US user clocks ...