Teenagers who experience high levels of stress and loneliness are significantly more likely to develop problematic internet use, according to new research that challenges the common assumption that screen time alone is the main culprit behind unhealthy online behaviour in young people.
The study, published in the journal Healthcare, examined 750 adolescents aged 13–19 in Croatia, and found that the psychological state a young person brings to the internet matters far more than the number of hours they spend on it. Researchers from the University of Zagreb and the Teaching Institute for Public Health of Split-Dalmatia County set out to understand not just how much teenagers go online, but why some develop compulsive and harmful patterns of use while others do not.
The findings revealed that stress and loneliness act as key psychological mechanisms that push adolescents towards excessive internet use as a way of coping with emotional distress. This supports an established theory in the field suggesting that teenagers turn to the internet to fulfil psychological needs that are going unmet in their offline lives, particularly when they lack the emotional skills to manage difficult feelings in healthier ways.
Not all online activities carried the same risk. Social media use and online shopping were associated with higher rates of problematic internet use, whereas simply browsing for information or reading online showed no such link. Online shopping remained a significant predictor of problematic behaviour even after accounting for stress and loneliness, which researchers suggest may reflect its connections to impulsivity and reward-seeking tendencies common in adolescence.
Importantly, the research identified emotional competence as a protective factor. Adolescents with stronger abilities to recognise, express, and regulate their emotions were less likely to develop problematic patterns of internet use, even when they spent considerable time online. This was particularly evident in relation to social media use, where emotional skills appeared to buffer against the risks associated with heavy engagement.
The study adds to growing concern among psychologists and public health professionals about teenager mental health and the internet. Problematic internet use in adolescents has been rising across Europe, with the World Health Organisation noting an increase in problematic social media use among young people from 7% in 2018 to 11% in 2022.
The researchers argue that prevention efforts must move beyond blanket restrictions on screen time and instead focus on building young people’s emotional resilience. School-based programmes that teach stress management, emotional regulation, and healthy coping strategies are likely to be more effective than simply limiting device access.
The cross-sectional design of the study means that cause and effect cannot be established with certainty, and the authors acknowledge that self-reported estimates of time online may not always reflect actual usage. Future research incorporating objective tracking data would strengthen these findings.
For parents, teachers, and policymakers concerned about adolescent internet addiction and teenage mental health, the central message is clear: addressing the emotional roots of problematic internet use is likely to achieve far more than counting screen hours.

