The news: Health warning labels discourage US teens and adults from using social media, according to a Stanford Medicine study published earlier this month in JAMA Health Forum.

Researchers tested several messages across 1,012 teenagers and young adults in the US:

• An explicit warning linking social media to health concerns such as youth mental health harms, negative body image, and sleep disruption
• A time-break reminder that did not mention health risks
• And an unrelated seatbelt-safety control message

Warnings referencing mental health concerns, depression, and anxiety were perceived as most effective at raising awareness of social media’s harms. Nearly every health-focused warning outperformed a screen-time break reminder similar to the one TikTok already uses. For context, the study did not measure actual changes in social media use. However, teens and young adults rated the warnings as more effective at discouraging them from wanting to use social media than a neutral control message.

Why it matters: The study follows years of research linking heavy social media use to depression, anxiety, poor body image, and disrupted sleep.

Research findings have prompted regulatory action to address the addictive nature and health harms of excessive social media use among young people.

• Then-Surgeon General Vivek Murthy called for tobacco-style warning labels on social media in 2024, and four states have passed laws requiring them, with California's taking effect Jan. 1, 2027.
• A bipartisan coalition of 42 state attorneys general petitioned Congress to enact warnings at the federal level.

California's own warning language, which was tested in the Stanford study, performed on par with the researchers' messages despite being longer and more dense. The wording was built to survive litigation from an industry that is challenging these laws in court.

Implications for social media platforms: The findings give lawmakers more evidence as warning-label regulations face industry legal challenges. Platforms should expect legislators in states beyond the ones that have already introduced similar bills to use mental-health-specific wording rather than generic screen-time messaging as they draft requirements.

A key unknown also remains: the Stanford researchers noted that social media warnings would function as pop-ups rather than permanent labels like those on cigarette packs, and it is unclear whether their effect holds once users learn to dismiss them. Expect follow-up research testing real-world behavior change instead of self-reported intent, as the next test of whether these mandates deliver lasting results.

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