As various studies reveal potential links between mankind’s ever growing collection of devices to issues of impaired vision, childhood depression, obesity and loss of sleep, Rob Leane looks into what damage our screens might be doing…
How many devices do you have? If you’re reading this, presumably you at least have a couple. Personally, I have a laptop, a smartphone, a Kindle and an iPod. I have a smart TV too, if you count that as a device. There’s rarely a point in the day – only mealtimes, some days – when I’m not interacting with one of these devices in one way or another.
You can imagine my fright, then, when I started reading about potential links between device usage and all sorts of health issues, from loss of sleep (one I do definitely suffer from, on occasion) to conditions far, far worse. Hearing that the technology that supplements my life could be harmful to my health was one of the scarier possibilities I’ve heard recently.
To try to get to the bottom of it – or at least to become better informed – I read up on all the theories in this field. This is what I found on my trawl around the internet…
Vision Problems
Beginning with one that we can all probably relate to, overindulgance in staring at screens can cause eyesight problems. Computer Vision Syndrome (or Digital Eye Strain, as it’s sometimes known) is a very real thing and is recognised by such high-profile organisations as the American Optometric Association (AOA).
It describes the condition as “a group of eye and vision-related problems that result from prolonged computer, tablet, e-reader and cell phone use.”
“Many individuals experience eye discomfort and vision problems when viewing digital screens for extended periods,’ its website notes. “The level of discomfort appears to increase with the amount of digital screen use.”
The AOA lists the most common symptoms of Computer Vision Syndrome as eyestrain, headaches, blurred vision and dry eyes. It also mentions neck and shoulder pain as a common complaint from the same patients. Sound familiar?
It certainly does to this writer. The specific reasons for these symptoms could apparently include poor lightning, the glare from your screen, improper viewing distances, uncorrected vision problems and poor seating posture.
So how can we avoid these symptoms? Well, we need to avoid the causes of them. If you’re meant to be wearing glasses for computer work, then try not to forget. Even if you don’t think you need them all the time, it might help reduce soreness and strain.
The way you view your computer is also important. The NHS tells us that “your monitor (screen) should stand at eye level or just below it.” The AOA adds that your screen should ideally be no more than 28 inches away from your eyes. Any closer than 20 is considered too close, though. Looking from documents on your table to a high up screen can also cause extra strain, so we should try to keep everything we need to look at on a similar level.
The AOA also recommends a few simple routines to help keep your eyes from hurting. After two hours of continuous computer use, it advises 15 minutes of rest time. Every 20 minutes, it could also help to move your focus away from the computer for just 20 seconds. Focus on something in the distance instead, give your peepers a break. Blinking frequently is also recommended.
Lighting issues also play a part. Try to minimise the glare on your screen. This can be achieved by repositioning yourself in the office or simply by turning your computer screen away from glarecausing sources of light.
Trouble Sleeping
Although some of us love nothing more than digging our teeth into a good ebook (on a Kindle or similar device) before nodding off, experts have also found links between device usage and trouble sleeping. Dr Mari Hysing, of the Norwegian research centre Uni Research Health, led a study into this area, specifically focusing on how devices affect teenagers’ sleep patterns.
Gathering data from 10,000 16- to 19-year-olds (before publishing her findings through the online journal BMJ Open), she found that teens who spent more than four hours a day looking at screens had a 49% greater risk of taking a full hour to fall asleep. Additionally, these more device-happy youngsters were 3.5 times more likely to sleep for under five hours a night. The reasons for this seem to point towards the nervous system and the body clock. Somehow, over-use of devices is seemingly correlating with bad sleep.
Resultantly, the study concluded with a suggestion that health authorities should update their guidance on matters of daily screen usage for young people.
Hysing’s personal advice – shared online by the Independent – is that “parents should be aware of the use of all types of electronic devices in the bedroom.” She urges parents to, “At a minimum, keep the nighttime screen-free in the bedroom, and ideally be logged off an hour or so before they go to sleep.”
The USA’s National Sleep Foundation (NSF) had similar findings, with Dr Charles Czeisler reporting that “artificial light exposure between dusk and the time we go to bed at night suppresses release of the sleep-promoting hormone melatonin, enhances alertness and shifts circadian rhythms to a later hour – making it more difficult to fall asleep.”
My basic interpretation of that scientific speak is this: by reading an ebook, playing a computer game or mucking around on your laptop, you’re encouraging your brain to think, not to relax. Therefore, it’ll take you longer to get to sleep if you keep using these devices later into the night. Interestingly, the NSF did also note that the passivity of your screen-based activity of choice (watching a TV show, rather than playing a game, for example) could alter the results.
Regardless, the NSF’s study concluded that, more often than not, “light-emitting screens are in heavy use within the pivotal hour before sleep. Invasion of such alerting technologies into the bedroom may contribute to the high proportion of respondents who reported that they routinely get less sleep than they need.”
The NSF’s advice to counter this is simple – plan your bedtime where possible, and get in a screenfree hour before that. If you find it difficult to switch off, keep a pen and paper by the bed to jot down any thoughts that you need to act on tomorrow, rather than dwelling on them now.
Pretty much ruining my freelance lifestyle in the process, the NSF also recommended avoiding naps of longer than 45 minutes after 3pm – damn!
Obesity
Overuse of screens has also been linked to childhood obesity by Dr Leonard Epstein and his colleagues from both the University of New York and the Stanford Prevention Research Centre in California. In 2008, news outlets around the world shared the group’s findings.
Supported by the US National Institute of Diabetes and Digestive Diseases, Epstein et al had studied 70 children and the way their use of technology correlated to their fitness and health. They achieved this by splitting the children into two groups – some with limited screen time, the rest with unlimited access to TV and computer games. The study ran for two full years.
The children with strict controls on their use of devices (they were allocated a weekly budget of ‘screen time’, which was gradually reduced over the course of the study) made drastic changes to their routines, reducing their screen time by 17.5 hours per week, on average. In contrast, the group with unlimited screen time only reduced their habits by an average of 5.2 hours per week.
Tellingly, those who had their screen time limited became the healthier children. Their daily energy intake was significantly less (around 200 kilocalories, on average), and their BMI score was also better, by around 0.1 units.
The researchers concluded that “reducing television viewing and computer use may have an important role in preventing obesity and in lowering BMI in young children, and these changes may be related more to changes in energy intake than to changes in physical activity.” Essentially, less screen time equals less food and drink consumption, which equals less weight gain.
However, this study did have its limitations. For one, the children studied were all taken from the 75th percentile of BMI for their age. The results would have differed in children who were less overweight to begin with. Also, the study couldn’t account for screen time outside of the home. There was nothing to stop children playing games or watching movies at their friend’s houses. Also, exact food diaries were not kept, which could have provided important insights.
“Screen time appears to be an important modifiable cause of childhood obesity,” wrote the NHS in its analysis of this study, “but exactly how it exerts an effect remains to be established.”
As this study has shown that less TV does not necessarily increase physical activity, parents who want to get their children doing more healthy physical activities may have more success presenting it as a fun first choice, rather than just as an alternative to watching TV.”
There is some correlation between obesity and screen time, then. Of course, though, it’s possible to spend a lot of time online and to lead a healthy lifestyle.
Depression
In 2013 – much more recently than that obesity study – another set of scientists, from Public Health England (PHE), decided to investigate the relationships between young people their devices. This time, though, they were searching for correlation between screen time and childhood depression.
Sadly, after studying research conducted by the Children’s Society among 42,000 eight to 15-year-olds, they did find a correlation, which they published in a report titled ‘How healthy behaviour supports children’s wellbeing.’ Again, the press shared this report widely. On the Independent website, I found some particularly worrying excerpts from PHE’s report.
Professor Kevin Fenton, Director of Health and Wellbeing at PHE, found that “the greater the time spent in front of the screen, the greater the negative impact on both behavioural and emotional issues relating to the child’s development.”
“Higher levels of TV viewing are having a negative effect on children’s well-being, including lower self-worth, lower self-esteem and lower levels of self-reported happiness,” read the report.
PHE also noticed a concept that they named a ‘dose-effect’ regarding young people’s screen time, which means that “each additional hour [or ‘dose’] of viewing increases children’s likelihood of experiencing socio-emotional problems and lower self-esteem.”
Lily Caprani – PHE’s Director of Policy – told the Independent that social interaction via a computer or mobile phone did not deliver the same benefits in emotional wellbeing as real human interaction. “It’s nowhere near,” she said. “You have to be physically present with your friends to get the benefits of social interaction. Texting, Facebooking or even chatting on the phone has a remoteness that means you lose a lot of the positive impact.”
Increased exposure to TV (“consistently associated with reduced feelings of social acceptance, and increased feelings of loneliness, conduct problems and aggression”) and videogames (“children who spend more time on computers and playing video games tend to experience higher levels of emotional distress, anxiety and depression”) in place of real social interaction is clearly something to worry about among young people, then. It’s always worth remembering there’s no replacement for a healthy physical and social lifestyle.
Other studies have looked at ‘screen addiction’ and its physical effect on the brain. Different studies – compiled effectively in Victoria L Dunckley MD’s ‘Psychology Today’ blog entitled ‘Gray Matters: Too Much Screen Time Damages The Brain’ – have found cases of various worrying brain symptoms in the brains of screen addicts.
These include grey matter atrophy (shrinking of the area where processing occurs), impaired cognitive functioning (less efficient information processing), and impaired dopamine function (to do with addiction and reward processing). For more information, see Dunckley’s blog. The long and short of it is this, though: our screens can be addictive, and in the worst cases of this, human brains can really suffer.
Lessons Learnt
By this stage, you’ve probably got the gist” spending all your time on your devices isn’t considered to be good for you by any stretch.
Using your devices before heading to bed can interrupt healthy sleeping patterns. Sitting at your computer all day without taking breaks can cause problems with eyesight. In young people, there’s been correlation found between overuse of screens and both obesity and depression. For screen addicts, the brain can physically suffer too.
Writing this has certainly been an eye-opening experience for me, and I’ll definitely be trying to learn some lessons from my research here. It’s left me thinking: what’s the biggest takeaway from all of this?
Well, essentially, it seems like the most important lesson here this: it’s vital to distance ourselves – and any young people we might be responsible for – from our devices, at least for a few chunks of the day. In children, over four hours daily seems to be considered overdoing it, from quite a few scientific sources.
Obviously, in adulthood, restricting computer usage to less than four hours is pretty much impossible. If you’re reading this, you probably work at a computer, and most of you may not have a say in the hours you spend at your desk.
However, you can hopefully add in a few breaks, make sure you’re working in the best environment possible and save some time every evening to be device-free. Exercising, healthy eating and some in-person social interaction are all good habits to keep up too.
All in all, then, it may be tempting to live your life exclusively through your consoles, tablets, computers and smart devices, but it’s important to do other stuff too. You probably all knew that already, but now we have some specific evidence to back it up. Right, I’m off for a walk…