(Image: Bernhard Lang/Getty)
Text neck, Candy Crush thumb, iPad hand – the list of screen-related ailments is growing. Add in claims the internet is rewiring our brains, and the 4 or 5 hours a day we spend poking at phones and tablets starts to look like a health risk.
Most of these problems have a quick fix, though. Let’s take the physical injuries. Text neck – looking down at a screen in your hands – puts strain on your upper back. Surgeon Kenneth Hansraj at New York Spine & Rehab Medicine claims that dropping the chin by 60 degrees is equivalent to making the spine support an extra 12 kilograms. And long periods spent jabbing and swiping or holding a tablet in an awkward grip can lead to stress injuries in the hands and thumbs. The compulsive playing of video games can also reduce pain sensitivity, meaning you could be damaging yourself without realising it. So keep your chin up and take regular breaks, regardless of how you feel at the time.
There are more subtle problems, too. Screens are strong emitters of blue light, which inhibits the production of the sleep-promoting hormone melatonin (see diagram). So using them in the evening can shift our circadian rhythms out of whack, and even cause insomnia. In one study, Anne-Marie Chang and her colleagues at Harvard Medical School got volunteers to read from either an iPad or a book for four hours before bedtime over two weeks. When reading from the iPad, melatonin secretion was delayed by an hour and a half. The volunteers also felt more tired the next day compared