Recent evidence shows that social media use has negative effects on well-being of children and youths. However, the underlying reasons are unclear, as social media are means that can also serve beneficial purposes. We propose the hypothesis that social media induce users to harmful addiction of a new variety because such use is not toxic per se but becomes toxic by crowding out beneficial activities. We identify, in particular, the key mechanism in the change of time preference: While social media induce users to present-biassed activities, thus encouraged by how platforms are designed, they crowd out activities that develop skills and are forward-looking, such as education, volunteering and democratic participation. This triggers a vicious circle leading to a long run deterioration of well-being and skills that would have acted as an antidote to addiction. As implication, policies should address adequate information and education in general, as well as increased competition in the digital platform market. While the available evidence supports our hypothesis in many respects, more empirical research is needed.

Published here.

(Abstract with IA podcast summary) Many educational institutions and experts have raised the alarm on the observation that social media use is dangerous for young people’s well-being and mental health. However, existing reviews on this issue do not provide definite answers that address the problems of causality and heterogeneity in social media use. This paper selects, reviews and discusses empirical studies that more rigorously analyze causality in the field using large samples and objective data over long stretches of time, while overlooking the heterogeneity problem. These studies adopt the ‘natural experiment’ approach to study staggered access to social media across the territory. The conclusion drawn for findings across the US, the UK, Germany, Italy and Spain is that social media generally harms young people’s well-being and mental health. In discussing these studies, which belong to the economics literature, the present paper suggests a novel theoretical interpretation: social media use becomes harmful because it displaces beneficial activities aimed at achieving future and pro-social purposes which would make young people less vulnerable to addictive use of social media. Supporting evidence emerges from reviewing studies that pay attention to causality. The paper thus makes evident the need for research to integrate different methods and disciplines focused on such a complex and urgent issue.

Published and downloadable here, with IA podcast summary (the second most downloaded article of 2025 – 12,600 up to now)