In a groundbreaking meta-analysis published in the prestigious journal JAMA Internal Medicine, researchers from the University of North Carolina Lineberger Comprehensive Cancer Center have shed new light on the effectiveness of e-cigarette warnings appearing on product packaging and advertising. With vaping continuing to surge in popularity, especially among young adults, this study represents a critical step in understanding how to communicate the potential health risks of e-cigarettes effectively, thereby influencing public behavior and potentially curbing vaping rates. The analysis, led by Seth M. Noar, PhD, rigorously synthesizes data from 24 studies involving over 22,000 participants, providing robust evidence on how text-only warnings influence perceptions and behaviors related to e-cigarette use.
The research underscores a compelling distinction between types of warnings. Specifically, health harm warnings — such as those highlighting the exposure to harmful chemicals during vaping — were generally more impactful than warnings focusing solely on addiction. While addiction warnings are presently mandated by the U.S. Food and Drug Administration and featured on many vaping products, this meta-analysis reveals that broadening the scope to encompass a variety of health hazards enhances effectiveness. Participants exposed to health harm warnings reported greater awareness of the risks and showed stronger intentions to quit vaping. This insight is pivotal in informing public health policies aiming to optimize warning messages and reduce vaping prevalence.
Methodologically, this comprehensive meta-analysis is notable for its inclusion criteria, which required studies to compare text-only e-cigarette warnings against either no warning or control warnings irrelevant to health risks (for example, messages about littering). This approach isolates the effect of warning content itself without confounding from extraneous messaging. Spanning studies published between 2007 and 2024, the analysis focuses exclusively on text-based warnings, excluding more graphic or image-based approaches, thereby emphasizing the potency of straightforward textual communication. The median age of study participants was 28, suggesting applicability across young adult populations that are at higher risk for vaping initiation.
One of the paramount findings of this study is its clarification around a common public health concern: the potential for e-cigarette warnings to create misperceptions about relative risks compared to combustible cigarettes. The meta-analysis found no evidence that warnings increased the false perception that e-cigarettes are more harmful than traditional cigarettes. This is a crucial nuance because effective risk communication must discourage vaping without exaggerating harm to the point of inadvertently encouraging conventional smoking, which is associated with greater health risks. This balance highlights the delicate task public health communications must perform in the tobacco harm reduction paradigm.
The study’s findings carry significant implications for regulatory agencies worldwide. Presently, the U.S. mandates only a single addiction warning on vaping products. However, the authors advocate for the adoption of multiple, rotating warnings, similar to the policies adopted in Canada and other countries. Rotating warnings can address the multifaceted risks of tobacco product use, thereby maintaining public engagement and awareness. The Canadian approach, which explicitly warns that vaping products release chemicals potentially harmful to health, is used as a successful model. Such policies could enhance the effectiveness of warnings and ensure that diverse health risks are communicated clearly to both current e-cigarette users and the broader public.
Despite the promising results, the researchers also acknowledge challenges regarding the visibility and persistence of warnings. One noted problem is that many users discard product packaging after initial purchase, which diminishes exposure to warnings over time. Furthermore, given social behaviors such as sharing devices at gatherings, some users may never encounter warnings at all. To address this, the study suggests exploring additional warning placements, including affixing warnings directly on devices themselves. This innovation could ensure repeated and unavoidable exposure, further reinforcing risk messages and potentially amplifying their impact on behavior.
From a theoretical standpoint, this meta-analysis contributes to the literature on health communication by demonstrating that simple textual warnings — when well-designed and strategically deployed — can be potent tools for influencing perceptions and intentions. The reliance solely on text challenges the assumption that graphic labels or imagery are necessary to achieve behavioral influence. As tobacco product landscapes evolve, especially with the proliferation of novel nicotine delivery systems, understanding and harnessing text-based warnings become integral components of comprehensive tobacco control strategies.
Moreover, the quantifiable effects analyzed through this meta-analysis — including increased perceptions of harm and addiction, as well as behavioral intentions to quit — provide a rigorous evidence base upon which regulatory and public health decisions can rest. With over 22,000 participants pooled across studies, these results are highly generalizable, reinforcing confidence in policy recommendations. The evaluation metrics used, ranging from perceptual changes to intentions, align with established behavior change theories, supporting the causative link between warning exposure and motivation to quit or reduce use.
Seth M. Noar, PhD, who serves as the director of the Communicating for Health Impact Lab at the Hussman School of Journalism and Media, emphasizes the real-world value of these findings. He notes that these findings not only inform policy but also offer critical insights into public health messaging strategies that can be adapted to other emerging tobacco products. Importantly, he highlights ongoing research priorities aimed at optimizing warnings, including experimenting with placement, messaging content, and integration with broader tobacco control efforts.
Complementing Noar’s perspectives, Youjin Jang, PhD, a postdoctoral researcher and first author of the article, stresses the novelty and practical relevance of the results. She articulates that expanding text-only warnings to include explicit information about chemical exposures and other health hazards represents a crucial next step for regulatory science. This recommendation reflects an intent to move beyond addiction-centric messaging toward a richer depiction of health consequences associated with vaping, which could resonate more strongly with consumers.
In totality, this meta-analysis marks a significant advance in understanding how to utilize warnings to mitigate the public health risks posed by e-cigarettes. As vaping continues to reshuffle the tobacco product market and challenge traditional regulatory frameworks, evidence-based communication approaches such as those identified here become indispensable. Future research on graphical innovations, device-specific warnings, and the intersection of social media messaging will undoubtedly build upon this foundation, ultimately striving to reduce nicotine addiction and tobacco-related disease on a global scale.
The publication of these findings in JAMA Internal Medicine on June 2, 2025, not only provides academic validation but also draws attention from regulatory bodies, health advocates, and policymakers seeking to harness science-based strategies to protect public health. This rigorous synthesis reaffirms that direct, clear, and evidence-informed warnings hold substantial promise in steering public perceptions and behaviors regarding e-cigarettes, illuminating a pathway forward in the evolving landscape of tobacco harm reduction.
Article Title: Effectiveness of Text-Only E-Cigarette Warnings A Meta-Analysis
News Publication Date: 2-Jun-2025
Web References: https://jamanetwork.com/journals/jama/fullarticle/10.1001/jamainternmed.2025.1380
References: Meta-analysis encompassing 24 studies published 2007–2024 involving 22,549 participants.
Image Credits: UNC
Keywords: Public health, Oncology, Health care policy, Addiction
