Children’s mental health under attack by the smartphone

Wellbeing of younger people started to take a dip in 2012 when one of the world’s most powerful devices became widely available

My old stomping ground, the biochemistry department, is located in UCC’s largest building, the Western Gateway. The long ground-floor central corridor I walk along to reach the lifts is studded with benches where students sit between lectures gossiping and laughing – except I see little gossiping and laughing nowadays. Most students sit eerily silent, staring at their smartphones.

Knowledge of how the natural world works uncovered by science is used to make useful devices (technology) such as radios, antibiotics, computers and smartphones. Most technology is used to do good in the world, eg antibiotics. However, some technological devices are abused by end-users and do more harm than good. One such device is the smartphone, in itself an amazingly powerful, versatile and useful tool but, when married to social media, it is threatening to produce a worldwide collapse of youth mental health.

In broad terms, social media is digital technology allowing the sharing of ideas and information, including visual and text, through virtual networks and communities, featuring user-generated content encouraging engagement via likes, shares, comments and discussion. More than five billion people use social media worldwide. The largest social media platforms are Facebook, WhatsApp, YouTube, Instagram, WeChat, TikTok. Smartphones allow us to carry all this social media in our pockets, available 24/7.

San Diego State University psychologist Jean Twenge has collated a huge amount of data indicating the many harms caused to children and teenagers specifically through use of social media on smartphones – Smartphones Are Damaging Our Kids | National Review. This data includes a range of wellbeing measures, including sleep patterns, socialising, indicators of loneliness/depression and participation in adult activities. Much of this data was summarised by John Burn-Murdoch in the Financial Times last year.


Youth mental health is collapsing and the inflection point on the curve everywhere is around 2012. No prizes for guessing what happened around 2012 – smartphones graduated from the luxury category to become commonplace

The percentage of American teens socialising with friends twice or more per week was fairly steady over the past 50 years until 2008 when it started to decline, falling very steeply from about 2012. This percentage dropped from 80 per cent in 1976 to 55 per cent in 2021 for 17 year olds. The percentage of 13–17 year olds sleeping less than seven hours a night stood at about 35 per cent from 2003 to 2013, when it sharply took off, rising to 50 per cent by 2022. The percentage of American 12-17-year-old girls with big depression was steady at about 12 per cent until 2011 but rose to almost 30 per cent by 2021. Meanwhile the share of American teens who say they are “constantly online” has now risen to 46 per cent.

And, it’s not only in United States – this pattern is consistent and universal. The percentage of 15 year olds scoring high in loneliness in Asia, Latin America, Europe and English-speaking countries sharply increased in about 2012. Rates of depression among French 15-24 year olds have quadrupled in the past 10 years.

Youth mental health is collapsing and the inflection point on the curve everywhere is around 2012. No prizes for guessing what happened around 2012 – smartphones graduated from the luxury category to become commonplace. Today everybody owns a smartphone and the average American teenager spends nearly five hours a day on social media.

Twenge has considered other possible causes of these disheartening teen wellbeing statistics, eg anxiety over global warming, college debt, drug-use etc but none of them fit the bill. There is no doubt that use of social media on smartphones has a huge negative influence on the lives of teenagers.

What should be done about this problem? Twenge proposes a ban on the use of social media for all under-16s. This would protect the very vulnerable younger teens until they mature sufficiently not to be significantly harmed. Several US states now require parental permission before under-16s can get social media accounts.

This issue evokes memories of how tobacco smoking was tackled. Once a highly popular social habit, smoking was revealed to be a leading cause of lung cancer in the 1960s. Public health campaigns to persuade people to stop smoking were fought long and hard and opposed by the big tobacco companies.

Bans on radio/TV advertising of tobacco, strict age limits on cigarette sales and smoking bans in indoor public areas were introduced. These efforts gradually succeeded – in the UK smoking has continuously declined over the past 50 years by about two-thirds. A similarly hard battle will be called for to control social media use among young people.

William Reville is an emeritus professor of biochemistry at UCC