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Kids and screen time: How much is too much for children?

A child staring at a tablet screen while in bed.

You check in to say good night to your son only to find he is playing "Fortnite" in bed.

Or your daughter is busy texting when she is supposed to be studying.

Children and their phones are inseparable today, and all that reading and playing games on their handheld devices may be harming their vision.

To reduce screen time, some parents ban phones at the dinner table. This applies to both adults and children. And in some homes, playing games or texting must stop two hours before bedtime.

To put a hard stop on screen time, some parents set time limits on their children's daily device use. For example, when a total of two hours of screen time has been reached, no more texting, game playing or YouTube watching.

Definition of "screen time"

"Screen time" refers to the amount of time a person spends staring at the digital displays of computers, tablets (iPads, for example) and smartphones.

World Health Organization guidelines issued in early 2019 recommend no screen time for children under 3 and screen time of no more than 1 hour for children ages 3 and 4. "Less is better," the WHO recommendations say.

The Royal College of Paediatrics and Child Health, however, recommends that decisions on how much time with digital devices is appropriate be made on a case-by-case basis within families. Some screen time can help children learn, researchers noted.

According to the RCPCH's 2019 screen time study, there are clear indications that too much screen time does have harmful effects on children.

More screen time equals less healthy diet: Children who spend too much time playing games, texting or watching videos often don't eat nutritious foods and have a higher propensity for obesity.

Screen time can be depressing: Children who spend more than two hours per day in front of their screens tend to have more depressive symptoms. Screen time isn't all bad, though. Some studies have found that some screen time is better for mental health than none at all.

The RCPCH study included the comments of 109 children and young people aged 11-24 from across the UK.

How much time did these UK youths spend on their devices in a given day?

2.5 hours on computers, laptops and tablets
3 hours on their phones
2 hours watching TV

Risks of too much screen time for kids

When talking about the risks of too much screen time for kids, we’re basically talking about the potential harmful effects of too much blue light.

The LED screens of computers and portable digital devices emit a broad spectrum of visible light. Most of these light rays are harmless, but a portion of the light emitted by these screens is relatively high-energy visible light called "blue light." Blue light has shorter wavelengths and higher energy than other visible light rays. And laboratory research suggests certain bands of blue light may be harmful to the light-sensitive retina of the eye over time. Blue light also plays an important role in regulating our body's circadian rhythm. This basically is an internal clock that's running in our brain and cycles between alertness and sleepiness at regular intervals over a 24-hour period. It's also called our sleep/wake cycle. Too much exposure to blue light at the wrong time of day can disrupt a person's normal sleep/wake cycle, which can have serious health consequences.

All of this begs the question: Should there be different limits on screen time based on a child's age? The RCPCH review notes that the developmental, physical and sleep needs of children do vary with age, and this will impact the decisions that families make about screen use.

How to cut back on screen time

So then, what can a parent do to prevent harm to their child's eyes (and overall health) from too much screen time?

It's unlikely kids will reduce their use of digital devices. So the answer lies in taking steps to limit the amount of blue light reaching their eyes while they are using these devices.

Spectacles and sunglasses to reduce blue light

The sun emits much more blue light than digital devices. All kids should wear sunglasses outdoors to reduce their lifetime exposure to harmful blue light.

One solution is to purchase spectacles with lenses that reduce the amount of blue light that enters the eyes from computer, tablet and smartphone screens. A number of lens manufacturers produce lenses that filter blue light.

Another option is to have an anti-reflective coating that blocks blue light applied to the lenses.

A third option is to purchase glasses with photochromic lenses. These sun-sensitive lenses block some blue light indoors and have the added advantage of automatically blocking additional blue light from the sun outdoors without the need for a separate pair of prescription sunglasses.

Yet another option — and the best option for superior protection from harmful blue light from the sun — is a pair of polarised sunglasses for outdoor wear.

Set limits on screen time

The RCPCH recommends that families "should negotiate screen time limits with their children based upon the needs of an individual child, the ways in which screens are used and the degree to which use of screens appears to displace (or not) physical and social activities and sleep."

To reduce the risk of your child disrupting his or her sleep/wake cycle, create a "no-screens" rule at least an hour or two before their scheduled bedtime.

Or set a time limit on your child's phone use. Apple, Google and other tech companies have recently introduced time management features and apps that allow you to monitor your child's daily screen time. Visit your phone manufacturer's website or store to learn more.

Be proactive as a parent. One goal maybe? Spend more quality time together and less screen time with your son or daughter left to their own devices. Better yet? Protect your child's vision while they're watching YouTube videos, posting Snaps and playing games.

Finally, schedule annual eye exams with an eye doctor near you to monitor your child’s vision and eye health. And don't forget to ask your optician about blue light protection options.

Page published on Tuesday, 25 June 2019