Children are growing up on screens. Experts warn their bodies are paying the price

Sunday, 5 April 2026

Children are spending more time than ever on phones, tablets and laptops. Now physiotherapists and optometrists are raising the alarm that they are seeing the consequences in young bodies: bent spines, worsening eyesight and a health burden building in plain sight. Amelia Wade reports.

Rob Knight thinks we are making the same mistake with devices that earlier generations made with smoking.

In the 1950s, he says, doctors could see the early warning signs at the coalface — a few worrying coughs, a few symptoms that did not yet seem like a crisis. It was only decades later that the true scale of the harm from cigarettes became impossible to ignore.

Knight, the lead physio for the New Zealand Breakers basketball team, believes the same thing is happening now, only this time the culprit isn’t cigarettes, but screens.

“The stuff we see in the clinic with the kids right now is just the tip of the iceberg.”

What physios and physicians are seeing now is what is coming for the health system 20 years from now, says Knight.

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It has left him increasingly alarmed by what he sees as an overlooked physical epidemic: children and young people developing postural changes, neck strain and musculoskeletal problems from the hours they now spend hunched over phones, tablets and laptops.

This is not simply a matter of slouching or looking bad, he says. It is the beginning of structural change in young bodies that may not fully declare itself until years later, when today’s children are adults living with pain, degeneration and disability.

“The tidal wave is coming,” he says.

At the centre of Knight’s concern is forward head posture — the now-familiar position of the head jutting in front of the shoulders as someone bends over a screen.

In a healthy posture, he says, the ear should sit roughly in line with the shoulder. But once the head - which typically weighs up to six kilograms -moves forward, the load on the neck and spine increases dramatically.

“For every 2.5 centimetres forward … your head weight doubles,” he says.

That loading does not just affect the neck. Knight describes a chain reaction through the body: strain on muscles and ligaments, compression through the front of the spine, weakening of the structures that help hold the body upright.

“It’s like pitching your tent with a piece of elastic,” he says. “It just doesn’t work.”

He says the consequences go well beyond a rounded back. Forward head posture can contribute to headaches, jaw dysfunction, neck pain, shoulder problems, breathing issues and lower back pain as the rest of the body compensates.

Knight is especially worried because he says he is seeing the sort of postural changes in children that used to be associated with much older adults.

“We’re actually seeing this in kids now,” he says. “That’s not me being hyperbolic.”

A 2018 cross-sectional study of 300 school students aged 12 to 16 in Gujarat, India found 63% had forward head posture, including 56% of boys and 71% of girls.

The authors said the high prevalence suggested a potential risk of later musculoskeletal conditions affecting the cervical spine and shoulder.

That does not prove the same rates exist in New Zealand but Knight says the posture itself has become so normalised here that people often stop seeing it altogether.

He points to teenagers at bus stops bent over their phones and office workers curled over desks.

He cannot go to a cafe without seeing the postural epidemic everywhere. Sitting with the Sunday Star-Times, he pointed out dowager’s humps and tech necks on almost everyone who passed our table. Then he turned on this reporter’s hump and took side-on photos to prove the point.

“Our generation looks like old people,” he says.

But the health system isn’t aware of the burgeoning problem because the young often do not feel the consequences yet.

Teenagers can spend long periods in poor positions without the pain that might force them to change. Their bodies still tolerate a lot but Knight says that does not mean the damage is not happening.

That is why he keeps returning to the smoking analogy - teenagers smoking in the 1950s were not all getting lung cancer on the spot. The reckoning came later.

Knight says posture may follow the same pattern: low immediate alarm, high delayed cost.

There are already signs neck and upper-back problems are already imposing a growing burden in New Zealand.

ACC data provided by Knight show a steady increase in both the number and cost of claims related to upper back and neck injuries over the last two decades.

Between 2002 and 2022, new claims rose from 104,767 to 146,959, while active claims increased from 124,790 to 183,657.

Over the same period, the associated cost rose sharply — from $110 million in 2002 to $205 million in 2012 and $423 million in 2022, roughly doubling each decade.

That data does not show devices are the cause. But it does show neck and upper-back injuries are becoming more common and more expensive — exactly the sort of trajectory Knight says should ring alarm bells.

But the effects of screen-heavy childhoods may not stop at the spine.

Optometrists say they are also seeing worrying changes in children’s eyesight.

At Specsavers Sylvia Park, optometrist partner and director Arshad Hoosen says he is seeing more children present with short-sightedness, often from about age four onwards.

Some parents are shocked by how quickly prescriptions worsen.

“A kid can have a low prescription at a younger age, but that can significantly climb as the years go up,” he says.

“At age five it was a lower number, but by age seven or eight it might have doubled or tripled in prescription.”

In Ponsonby, optometrist Ash Nath says the shift has become hard to ignore.

“I’ve noticed children as young as four years old, three years old become myopic,” he says.

“You know, seeing minus two, minus three prescription, which typically in the early 2000s and 2010s would be seen in an 18 to 19-year-old.”

The World Health Organisation considers myopia to be a rapidly rising public health crisis and predicts that half the global population will be affected by 2050.

Both optometrists say genetics still matter. A child with myopic parents is still at higher risk but children’s environment is now also playing a major role: long hours doing close-up work, sustained screen use and not enough time outdoors in natural light.

Hoosen says the issue is not just school devices, but the cumulative time piled on top through YouTube, gaming, social media and movies, often indoors and at very close range.

He believes Covid accelerated our children’s move inside and online.

“Myopia has always existed, even when there were just pens, pencils and books,” he says.

“But we’re seeing children adopting much more fun devices that are more addictive for longer.”

Nath says the concern goes well beyond children needing stronger glasses.

“Myopia is basically when your eyeball is a bit too long for its own good,” he says.

As the eye grows longer, the tissue at the back can be stretched which increases the risk of future eye disease and causes permanent damage which can impact on quality of life. Poor distance vision can also affect learning, sport, confidence and safety.

“It’s how they see the world, it’s how they play sport, it’s how they interact with their friends and the community,” Hoosen says.

“It does point to a big overall health and wellbeing aspect to it, let alone just vision.”

Julie Cullen, a paediatric physiotherapist and University of Auckland researcher, says the harms linked to screens go well beyond posture and eyesight.

Cullen co-authored a New Zealand review paper arguing the country needs best-practice recommendations for schools.

It found New Zealand students are among the heaviest users of digital technologies in the world and that frequent use has been associated with reduced learning outcomes, as well as risks to health and wellbeing including myopia, dry eye, back and neck pain, headaches, obesity and sleep disturbance.

For children over five, Cullen says harms were commonly reported in studies looking at roughly two to six hours a day of use. For younger children, the threshold is even lower.

“While screens are a big part of life, too much screen time is linked to a risk of harm to many areas of children’s health,” she says.

The problem is that children’s exposure is cumulative: school screens, homework and recreational use all stack up, Cullen says. She is arguing for clearer guardrails for schools as well as families.

“We want young people to benefit from the opportunities digital technologies provide, but with lower risk.”

Knight sees the same broader pattern from another angle. Schools may ban phones, but children still spend long stretches on school-issued devices. At home, screens have become entertainment, babysitters and social connection all at once.

All four specialists described the same danger: the harm is gradual, cumulative and easy to dismiss until it is entrenched.

“The parents are complaining hugely, because they see it in their teenagers. But the teenagers don’t complain much because they’re not really feeling it,” says Knight.

None of them argued for banning technology entirely. Hoosen says the issue is balance, not total omission.

“It’s not about omitting all these things from your kids’ lives, but just responsibly balancing it off,” he says.

Knight’s point is similar. Telling children to sit up straight is not enough. What matters more, he says, are active interventions - classrooms, furniture, routines and habits that stop children staying collapsed in one position for hours at a time.

“There’s no such thing as a good chair. It’s actually something that changes your position.”

For Knight, the bigger worry is that society is still treating these changes as cosmetic quirks or inevitable by-products of modern life, rather than warning signs.

“I can just see we have a huge problem coming that nobody is even acknowledging right now,” he says.

Knight says he’s seeing the damage accumulating in plain sight - in the bent necks, rounded shoulders and bodies of children growing up on screens.

Hoosen and Nath see it when young patients cannot see clearly across a classroom.

And Cullen sees it in the broader evidence linking excess screen exposure to poorer outcomes across health, development and wellbeing.

The experts are sounding the alarm because devices are not just capturing children’s attention.

They are reshaping their bodies.