Source: The Conversation – Canada – By Salima Kerai, Research Fellow, Centre for Global Child Health, The Hospital for Sick Children; Adjunct Faculty, Dalla Lana School of Public Health, University of Toronto
In a landmark decision, a Los Angeles jury has found that social media company Meta and video streaming service YouTube harmed a young user with addictive design features that led to mental health distress, including body dysmorphia, depression and suicidal thoughts.
Commentators have referred to this as social media’s “Big Tobacco” moment and further lawsuits are pending. The verdict has escalated calls for more regulation of social media platforms across jurisdictions.
Countries like Australia, France and Spain have already introduced age restrictions for social media use. Canada still lacks online harms legislation.
As parents campaign and policymakers consider how to address online harms, one crucial question is often overlooked: Why are teenagers so uniquely vulnerable to these platforms in the first place?
Dopamine hits to immature pathways
Imagine Sara, who at 14 was found unconscious on her bedroom floor after an attempt to take her own life. By every measure, she was thriving: strong in school, supported by family, living in a vibrant community. But behind her bedroom door, she was struggling with something no one could see. She spent hours scrolling, posting and chasing likes until the validation stopped coming.
A quiet sense of not being good enough slowly took root. Despite 150 online followers, she had no one she felt she could truly talk to. She became convinced she was completely alone.
Sara is a composite drawn from clinical and research experience, but her story is common. Like many teenagers, Sara turned to social media to connect, express herself and find a sense of belonging. At first, it felt good. Each quick hit of dopamine drew her back until the habit became hard to control.
Neuroscience shows that heavy social media use can overstimulate the teen brain’s still-developing reward pathways in ways similar to addictive behaviours like gambling.
This immature system also makes teenagers more sensitive to social feedback and less able to cope with rejection. This leaves them vulnerable to highs and lows of online interaction, including the rapid, repeated negative comments that can intensify emotional stress.
Read more:
Australia is banning social media for teens. Should Canada do the same?
Think of the teen brain as a highway under construction. The emotional expressway — the limbic system — is wide open for speeding. The pre-frontal cortex — the brain’s traffic-control centre responsible for judgment and impulse control — is still being built.
This imbalance means that the fast emotional traffic often outruns the signals from the control centre, creating traffic jams in judgment and rational thinking and making it harder for teens to pause, reflect and assess consequences.
Social comparison fuels anxiety
Social comparison deepens this strain further. As Sara scrolled through images of seemingly perfect lives, she felt increasingly inadequate. Envy, insecurity and fear of missing out chipped away at her confidence. At the same time, social media encouraged constant self-monitoring, as she tracked her likes, comments and appearance online.
Research links this kind of inward focus to higher levels of anxiety, especially in teens already under pressure.
Puberty adds another layer. During this stage, the brain becomes more sensitive to social and emotional cues. For girls, these changes often occur earlier and more intensely, helping explain why adolescent girls are disproportionately affected by social media-related anxiety and depression.
Connected online, disconnected in life
Most time spent on social media is not active or social — it is passive. Trial data in a case between the U.S. Federal Trade Commission and Meta show that only a small fraction of time on Meta platforms involves engaging with friends — about seven per cent on Instagram and 17 per cent on Facebook. The rest is mostly scrolling and watching rather than interacting. This results in an illusion of connection while deepening a sense of isolation.
Large studies across high-income countries consistently link heavy social media use to poorer physical health outcomes too, including shorter sleep and higher rates of obesity. Loneliness is a serious risk. The human need to feel seen and understood is fundamental. When it is not met, the body registers it as stress. Chronic loneliness has been compared to smoking 10 cigarettes a day in terms of its impact on health.
Many Canadian teens describe this paradox clearly: constantly connected online, yet increasingly disconnected in real life. They report pressure to present idealized versions of themselves and to keep up with peers. Online communication, they say, is easy to misinterpret, which can strain relationships and deepen isolation. They feel caught in a push and pull — drawn to connection, but often left feeling worse.
Now what? A call to action
We would not hand a 14-year-old the keys to a car without training, rules and safeguards. Yet we allow that same teenager unrestricted access to platforms designed to capture attention and maximize engagement.
The impacts on their physical and mental health are clear. Research involving more than 9,000 adolescents across eight countries found a strong association between problematic social media use and higher rates of depression and anxiety.
In Canada, suicide is the second leading cause of death for youth aged 15 to 24. Mental illness already costs us $51 billion a year, and 70 per cent of those affected show symptoms during adolescence.
Regulating social media is essential. And it requires a layered approach, much like road safety.
Platforms must be designed more responsibly. Age limits should be clearly defined and meaningfully enforced. And digital literacy education should help young people understand and manage their online experiences.
The question is no longer whether action is needed, but whether it will come in time to protect the next generation.
Salima Kerai does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
– ref. Neuroscience explains why teens are so vulnerable to Big Tech social media platforms – https://theconversation.com/neuroscience-explains-why-teens-are-so-vulnerable-to-big-tech-social-media-platforms-278521