The average toddler watches screens for up to 1.5 hours each day, while two thirds of 2-to-4-year-olds spend more than two hours in front of screens.
The average toddler watches screens for up to 1.5 hours each day, while two thirds of 2-to-4-year-olds spend more than two hours in front of screens.
It’s become common to use screens as electronic babysitters but an increasing body of research suggests it comes with risks. A new report reveals the downside for young kids who spend hours on screens. Science reporter Jamie Morton reports.
You’re exhausted from another chaotic day at work and you’recatching up on housework while scrambling to make dinner.
So, you do what many modern parents do: you leave the kids – quite literally – to their own devices.
“It may seem true in the short-term,” she says, “but children who are on screens when they are young are more likely to have issues with behaviour, language development, attention, sleep, and physical health.”
Here’s what the latest scientific research tells us about screentime for children.
We know that early childhood is a crucial time for building brains.
It’s a time for forming core skills like language, sensory processing and emotional regulation – all of which set us up for later life.
It’s why the Ministry of Health recommends parents keep their under-2-year-olds screen free – and limit screentime to a maximum of one hour for 2- to-4-year-olds.
As experts point out, it’s not just what kids are watching that causes issues – but how long they’re doing it.
In New Zealand living rooms and bedrooms, more than in most other countries, it tends to be too long.
Surveys tell us the average child under 2 watches screens for up to 1.5 hours each day, while around two-thirds of 2- to-4-year-olds spend more than two hours in front of screens.
University of Auckland researcher Julie Cullen, who recently led a major evidence review, said there were now studies pointing to developmental disruption, as well as behavioural issues like increased aggression and emotional outbursts.
Overexposed under-2s, according to one new paper she singled out, are more likely to develop sensory processing issues that make them sensitive to light and sounds.
It also leaves them seeking out other sources of stimulation, as Kathryn Berkett, a neuroscience trainer who works in schools around the country, spoke out about last month.
“Even programmes like Sesame Street have increased their editing speed,” said Berkett, who said the problem had put kids at risk of displaying behaviours that mimicked ADHD.
An in-depth report released on Thursday by Wellington-based think-tank Motu Research similarly warned of “significant” behaviour problems for preschool kids who’d been exposed to hours of viewing in early childhood.
It can derail learning
When the Government moved to ban phones in classrooms this year, it stirred debate over whether allowing screens in schools was ever a good idea.
That’s partly because devices have been so integrated in Kiwi classes that our kids have some of the highest measured rates of daily screen use in the developed world.
Experts stress not all of that’s bad: some types of screentime can help kids to learn – in small doses.
But simply having a phone nearby with notifications switched on, as a landmark UN report observed last year, could derail pupils’ focus for up to 20 minutes each time it buzzed or chimed.
As for the legacy of over-screening kids in early life, University of Canterbury researchers have observed how that could later mean weaker skills in things such as communication, counting and writing at school.
It steals sleep
It might be less surprising that screens are a big sleep-stealer for kids and adolescents.
Looking at phones into the night affects how quickly they fall sleep and also how long and well they sleep.
That owes to several factors, ranging from having had less physical activity, to bedtimes being pushed back, to blue light streaming out from screens and disrupting the natural release of sleep-inducing melatonin.
Many studies point to a “U-shaped” pattern where delayed sleep causes fatigue, leading to more sitting about and watching screens the next day.
While health guidelines tend to recommend no screens in the hour or two before lights-out, Otago University researchers have suggested the bigger problem is kids taking their phones and tablets to bed with them.
Researchers tell us a fifth of pre-schoolers aren’t getting enough sleep at a time they crucially need it for brain development – with TV and devices among the biggest culprits.
They found that every extra 10 minutes children spent using screens interactively in bed, such as for gaming, was 10 minutes of shut-eye they later lost that night.
Already, researchers tell us a fifth of preschoolers aren’t getting enough sleep at a time they crucially need it for brain development – with TV and devices among the biggest culprits.
“Most experts recommend that parents allow for a break between screentime and lights out so that children’s natural patterns aren’t disrupted,” Auckland University of Technology’s Professor Scott Duncan says.
It can lead to health issues
Duncan says there’s also evidence tying excessive screentime with less physical activity and obesity risk.
“This is because there are only 24 hours in every day: if children are on screens excessively then there is not enough time left to be active.”
Add to that a sizeable list of other physical health problems, including vision problems like myopia; back and neck pain; repetitive strain injuries; recurrent headaches and noise-induced hearing loss from headphones.
Data from the world-famous Dunedin Study has even linked excess TV-watching in childhood to developing metabolic syndrome – a cluster of conditions that include high blood pressure and excess body fat – several decades later.
Considering all the health risks, Cullen and colleagues recently called for screentime among 2-to-5-year-olds to be limited, with sessions lasting no longer than 10 to 15 minutes.
Cullen emphasises that she and other experts aren’t advocating for devices to be taken away from our young people.
“There are benefits to children and teenagers using digital technologies for learning, socialising and having fun,” she says.
“However, there’s broad agreement in the scientific community that along with benefits there are also harms to numerous areas of health and wellbeing.”
Screentime: How much is too much?
What the Ministry of Health advises:
*0-2 years: zero use
*2-5 years: less than one hour a day
*5-17 years: less than two hours
What NZ researchers recommend:
*0-2 years: no screen time
*2-to-6 years: minimal screen use, with maximum sessions of 10 to 15 minutes.
*6-12 years: no more than a third of school day on screens for learning, with more limited use for younger students (unless required for special learning needs).
*13-18 years: “intentional and balanced” use, with regular eye breaks and limits on headphones or earbuds.
Jamie Morton is a specialist in science and environmental reporting. He joined the Herald in 2011 and writes about everything from conservation and climate change to natural hazards and new technology.
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