What evidence exists to support restricting smartphone use for minors under 16?

Recently there has been a proliferation of Telegram and WhatsApp groups, made up of families and educators with thousands of participants, who are calling for delaying the age at which minors get their first phone to at least age 16. These initiatives, which have been publicised on practically all national media platforms, claim that various scientific publications link the use of these devices by young people with a variety of risks for their health and well-being.

The studies and reports consulted by Verificat, including meta-analyses and systematic reviews – publications that collect conclusions of studies on the same topic – have still not been able to establish what the right or most suitable age is for giving minors and adolescents a smartphone. Although it is true that numerous studies have associated the use of these devices among adolescents with an increase in mental health issues and decline in educational performance, this exhaustive analysis of the various papers shows, on the one hand, that it was not possible to prove that the negative consequences were caused directly by smartphone use and, second, that it is necessary to study the way the phones are being used, with all the nuances that entails. Let us explain.

There is no right age to start using a smartphone

Scientific evidence has not been able to establish an appropriate age for giving minors a phone. This was reflected in the most recent publication on the subject, an umbrella review of over 100 meta-analyses on the effects of screens shared this past Monday in Nature Human Behaviour. The paper argues that it is not possible, from a scientific perspective, to establish a single age for starting to use screens due to a combination of the developmental differences in childhood and adolescence and the diverse range of ways in which the devices are used.

“We believe that what children do with their devices is much more important than the devices themselves, so banning phones will most likely not address the root of the problem”, Taren Sanders, data scientist at the Institute for Positive Psychology and Education and leader of the aforementioned study, explained to Verificat in an email.

After reviewing the evidence available up to April 2023, the American Psychological Association (APA) arrived at the same conclusion with regard to social media use. The organisation points out, however, that the potential risks associated with these platforms – such as worse mental health, high-risk behaviours in real life, sexting or cyberbullying, among others – are greater if children begin using a smartphone between 10 and 14 years of age in comparison to 18.

“In addition to considering the age at which we give our child a smartphone, we also need to be asking ourselves questions such as: Is my child ready for everything having a phone entails? Am I, as a parent, ready to be present, to set limits, to defend those limits, to educate my child and be his or her best example? What does my child need the phone for?” María Salmerón, paediatrician and coordinator of the Digital Health working group of the Health Promotion Committee of the Spanish Paediatric Association (AEP), wrote in an email to Verificat. Salmerón also spearheaded the creation of a guide for best practices for using digital devices in families.  

Are smartphones truly harmful?

The conclusion of experts is that screens are not harmful per se, but that they present risks and opportunities that depend on the device, the way it is used and each person’s individual context. It is also the main conclusion of the review led by Sanders, which found that most uses had both positive and negative consequences for users’ health. The researchers found only detrimental effects fundamentally related to mental health, such as a higher risk of depression and risky behaviours, in the case of social media. They emphasise, however, that these effects are minimal.

“Issues such as depression and mental health are complex, and while the time spent in front of the screen could be part of the problem, it is certainly not the only variable”, the Australian data scientist said. His conclusions are similar to those of other umbrella reviews that have assessed the findings of systematic reviews and meta-analyses published on the topic, and that consider the associations between the use of screens and mental health to be “weak” and “inconsistent” (1, 2, 3).

The review of the reviews also finds detrimental effects of other phone uses, although weak associations are a recurring theme. For example, the researchers have found that the consumption of sexual content increases the risk of engaging in risky behaviours, that advertising ultra-processed foods increases caloric intake, and that the use of screens in general is only weakly associated with lower cognition. The experts say, however, that these findings do not allow us to make the generalisation that using screens is harmful to adolescents (and adults).  

“There is not enough conclusive evidence about the existence of substantial effects of using screen on well-being and health”, José César Perales, professor of Psychology at the University of Granada, summarised in statements to Science Media Centre España. However, he warned, “just as we cannot conclude that these effects exist, we also cannot conclude that they do not exist”. In his opinion, “it is too early to warrant disproportionate alarm about the use of screens”.

For María Salmerón of the AEP, however, there is already enough data to confirm that “we have a problem on our hands”. The paediatrician agrees that “we need to have more studies on the subject and dedicate more resources to research”, but points out that, in the meantime, “we cannot just look the other way”.  

Beyond the disparity of the results and the limited evidence, this field of research faces the additional challenge of depending exclusively on observational studies, which makes it difficult to determine cause-and-effect relationships. “We cannot know for sure whether, for instance, social media causes worse mental health or whether people with worse mental health are drawn to social media”, the Australian researcher concludes.