A compelling new study has followed thousands of Canadian teenagers for several years tracking associations between screen time use and depression. The research separated different types of screen time, and found while frequent television and social media activity correlated with increased symptoms of depression, video game and computer use seemed to have little negative effect.

It is entirely reasonable for parents to be concerned about the effects of screen time on their children's development and well-being. The rapid evolution of digital technology has resulted in a new generation being raised in front of a vast array of different screens. But, despite concerns, scientists haven't yet homed in on exactly what effect, if any, these screens are having on children. A new study out of Canada is offering valuable new data on this burgeoning topic, but as with many prior studies, its results are ridden with disclaimers and limitations.

The new research followed almost 4,000 children for an average of four years. At the beginning of the study the subjects were around 12 years of age. Each subject was asked to fill out a questionnaire every year, self-reporting on screen time use and mental well-being. Screen time use was split into four categories: social media, TV, video gaming and computers.

The temporal nature of the study allowed the researchers to examine any correlations that arose over time and the results were intriguing. A rise in symptoms of depression was associated with increases in both social media use and television viewing. Increased social media and television use was not linked to a decrease in outdoor physical activity, leading the researchers to suggest the rise in depression was more directly associated with a specific type of screen time use.

Strangely, however, the study did not see the same associated increase in depression alongside video game and computer use. The researchers hypothesize the reason behind social media and television potentially being more damaging to mental health is that these forms of media more realistically depict idealized versions of teens and adults, unlike the abstracted depictions seen in video games.

"Social media and television are forms of media that frequently expose adolescents to images of others operating in more prosperous situations, such as those with 'perfect' bodies and a more exciting or rich lifestyle," explains lead author on the study, Elroy Boers. "The algorithmic features of television viewing and, in particular, social media create and maintain a feedback loop by suggesting similar content to users based on their previous search and selection behavior. Thus, the more one's depressive state influences his or her viewing choices, the more similar content is being suggested and provided, and the more likely one will be continuously exposed to such content, thereby maintaining and enhancing depression."

While the way this study categorized different forms of screen use is undeniably a strength, it still suffers from the correlation/causation problem that hounds the majority of screen time research. Is the association seen in the data simply due to a depressed individual being more likely to use social media or watch television?

Gemma Lewis, a psychiatric researcher from University College London who did not work on this new study, agrees this new study does not allow for any causal conclusion to be made. In fact, Lewis questions how the subjects in the study were selected, suggesting these results may not be generally representative of all adolescents.

"The adolescents were originally selected for another study which was testing an intervention to prevent substance abuse, this means the individuals were chosen if they were at high-risk of substance use based on an assessment of their personality characteristics," says Lewis. "We know that many of the personality traits associated with substance abuse could also be associated with depression and therefore these adolescents are likely to have a higher risk of mental health problems than the general population of adolescents."

A major study published earlier this year from researchers at Oxford University came to the striking conclusion that digital technology use accounts for less than half a percent of a young person's negative mental health. Examining data from over 350,000 subjects in the UK and UK, that research found eating a good breakfast or getting a solid night's sleep had a more statistically significant effect on a teenager's mental health than their volume of digital technology use.

Ultimately, the research at this stage is way too disparate to come close to any conclusion over the effects of screen time on a child's mental health. If anything, the results of this particular study affirm the need for future research to get more granular in how it breaks down screen time. The concept of screen time being a single homogenous entity seems entirely redundant in our current digital world. Scrolling through Instagram, playing video games, or doing homework on a laptop, are all incredibly different activities, so limiting a child's screen time may need to be more specific than simply allocating a timed overall amount per day.

The new research was published in the journal JAMA Pediatrics.