Nanogirl Michelle Dickinson: How much is too much screen time?

More than 90 per cent of New Zealand teenagers aged 10-14 look at a screen or watch TV for more than two hours a day. Photo / 123RF

Do teenagers spend too much time on their screens? Some say 'yes' - they should put their devices down more; others 'no' - screen time is important to help prepare young people for a digitally-filled future.

New research out this week has added quantitative data to the debate, concluding that the ideal amount of screen is only one hour per day.

Previous studies have found high amounts of screen time to be associated with attention problems, school difficulties, sleep and eating disorders and obesity - although many of these studies have been small in terms of sample size and run over short time scales.

This most recent study, published in the journal Emotion, studied over 1.1 million teenagers aged 13-18 who had taken part in a large national study in the US. The study looked at the teenagers' psychological well-being, assessing traits including their self-esteem, life satisfaction and happiness.

They found that all three of those factors rose steadily from the 1990s and then dramatically dropped after the year 2012. The main change over this time was the percentage of teens who owned and used smartphones, which jumped from 37% in 2012 to 89% in 2016.

Wondering if the increase in smartphone usage correlated to the decrease in teenager happiness, the researchers looked deeper into the data. When analysing the number of hours the participants spent on their devices, they found a strong correlation between increased hours of daily screen time and decreased psychological well-being amongst teenagers.

The data also showed a distinct correlation between teenager happiness and non-screen activities - such as sports and in-person interactions - with those participating in more face-to-face activities reporting higher feelings of happiness.

The screen devices themselves are not necessarily 'bad'. Many teenagers in New Zealand attend schools which require students to be online using iPads, Chromebooks or other devices to do their work, and there is no evidence that this is harmful. The study considered 'screen time' as using social media, texting, gaming and videochatting.

Interestingly, a different study has shown that teenagers who spend lots of time interacting with screen devices are less able to read human emotions in others. These challenges around social interactions seem to come about in teenagers, who don't yet have the emotional tools to navigate through some of life's complications and confusions. This can exacerbate the difficulties of growing up.

Although this may sound concerning, the good news is that the issue seems to be fixable. The study took a sample group of teenagers away on an 'unplugged' camp for 5 days, encouraging them to have face-to-face interactions and banning all technology. At the end of the camp, the teenagers showed a significant improvement in their ability to identify a range of emotions in other people compared to the start of the week.

A gut reaction to these studies may be to just ban all teenagers from using screen devices to make them happier, but this isn't the solution - those teenagers surveyed who recorded having zero screen time were also unhappy.

The study concluded that the ideal screen time exposure to produce the happiest teenagers came in at between 1 and 5 hours per week, combined with high levels of face-to-face interactions through sports and hobbies.

So where does New Zealand stand in screen time use? Data from the Ministry of Health showed that in 2018 over 90% of New Zealand teenagers aged 10-14 look at a screen or watch TV for more than two hours per day, potentially putting them at risk of being less happy.

However, with our long, outdoor-filled holidays, perhaps a tech free summer camp is all that is needed to help our teenagers to reset and reengage with society.