Researchers at the University of Southern California’s Keck School of Medicine have found that e-cigarettes cause genetic alterations in oral cells more complex and variable than traditional tobacco, according to a study published in Frontiers in Oncology. The research, led by Jessica George, a postdoctoral researcher in the Department of Preventive Medicine, and Ahmad Besaratinia, professor of research preventive medicine and director of the USC Institute for Translational Genomics and Population Sciences, analyzed 83 adults—62 vapers and 21 non-smokers who had never used tobacco products. The study revealed that frequent vaping alters the activity of 3,124 genes, with flavor types and device designs playing a critical role in the extent of genetic changes. The findings were published in June 2026, following a three-year longitudinal analysis of participants recruited from Los Angeles County.
Besaratinia emphasized that the study’s methodology included RNA sequencing to assess gene expression in oral epithelial cells, a technique not previously applied in large-scale vaping research. “We were particularly interested in how different flavors interact with cellular pathways,” he said. “The results show that these interactions are far more dynamic than previously understood.” The team also noted that participants using devices with fruit or mixed flavors exhibited significantly more genetic disruptions compared to those using mint or neutral flavors. For instance, 31% of the observed gene alterations were linked to fruit flavors, while combinations of multiple flavors accounted for 64.3% of the changes. This contrasts sharply with traditional cigarettes, where genetic damage was less variable and more directly correlated with usage frequency.
Genetic Impact Varies by Device and Flavor
The study highlighted that the genetic effects of vaping are not uniform. Users of devices with fruit or mixed flavors showed significantly more genetic disruptions compared to those using mint or neutral flavors. For instance, 31% of gene alterations were linked to fruit flavors, while combinations of multiple flavors accounted for 64.3% of changes. This contrasts with traditional cigarettes, where genetic damage was less variable and more directly tied to usage frequency.
“The complexity of these genetic changes underscores the need to consider product-specific factors, not just usage patterns,” said Ahmad Besaratinia, a researcher involved in the study. “The variability in device design and flavor chemistry makes it challenging to establish clear regulatory guidelines.” The study also found that 60% of the altered genes were unique to e-cigarette users, suggesting distinct biological risks compared to conventional smoking. These findings align with earlier studies linking vaping to inflammation and DNA damage but expand on the role of product characteristics in driving these effects.
Dr. Jessica George, the lead author, noted that the study’s sample included individuals who had vaped for an average of 4.2 years, with a range of device types—from disposable pods to high-powered mods. “We observed that users of high-powered devices exhibited a higher prevalence of gene alterations associated with oxidative stress,” she said. The team also identified specific pathways, such as those involved in cell cycle regulation and immune response, that were disproportionately affected by flavored e-cigarettes. However, they cautioned that the long-term implications of these changes remain unclear.
Marketing Strategies Under Scrutiny
Separate research by Christina Watts, an associate professor of health policy at the University of California, San Francisco, and colleagues, published in Health Promotion International, revealed that the vaping and tobacco industries have aggressively targeted young people through appealing flavors, social media campaigns, and lobbying efforts. Watts, who has previously advised the World Health Organization on tobacco control policies, warned that these strategies risk creating a new generation dependent on nicotine. “The industry’s playbook has evolved alongside vaping technology,” she said. “Devices like mods, which allow for higher nicotine delivery and customizable flavors, have made it easier to bypass age verification systems and appeal to adolescents.”
For more on this story, see E-Cigarettes Alter 3,124 Genes, Study Finds Potential Cancer Links.
The study emphasized that marketing tactics have evolved alongside vaping technology, with devices like “mods” (rechargeable, high-powered e-cigarettes) further complicating regulatory oversight. Watts’ team analyzed over 1,200 social media posts and advertisements from 2024 to 2026, finding that 78% of them featured flavors marketed as “fruit-forward” or “dessert-inspired.” “These flavors are not just about taste—they’re designed to mask the harshness of nicotine and create a sensory experience that’s particularly appealing to young users,” Watts explained.
The research also highlighted the role of industry lobbying in shaping policy. Watts noted that between 2023 and 2025, vaping companies spent over $12 million on lobbying efforts in the U.S., with a focus on delaying flavor bans and weakening age verification requirements. “The rise of flavored e-cigarettes and advanced devices has made it harder to compare studies and develop consistent public health policies,” the researchers concluded. This trend has been exacerbated by the wide range of flavors available, which are often designed to mask the harshness of nicotine and attract younger users.
Regulatory Challenges and Calls for Action
The study’s authors and external experts have called for stricter regulations on e-cigarette flavors and device specifications. The research identified links between genetic alterations and serious health conditions, including cancer, endocrine disorders, and neurological issues. “These findings reinforce the urgency of addressing the risks posed by flavored vaping products,” said a spokesperson for the USC team. Dr. Besaratinia added that the study’s data could inform policy decisions, particularly in the U.S., where the Food and Drug Administration (FDA) has faced criticism for its slow response to flavored vaping products.
Regulatory agencies face a dual challenge: balancing harm reduction for adult smokers against the need to prevent youth initiation. The study’s results could influence future policies, particularly in the U.S., where debates over e-cigarette marketing and product standards remain contentious. The FDA’s Center for Tobacco Products has previously stated that it is prioritizing the review of flavored e-cigarette applications, but as of June 2026, no comprehensive ban has been implemented. “Without oversight, the current trajectory may lead to long-term public health consequences,” the researchers concluded.
Public health advocates, including those at the Campaign for Tobacco-Free Kids, have urged the FDA to take immediate action. “The genetic evidence is clear: flavored e-cigarettes are not a safe alternative to smoking,” said Matthew Myers, president of the organization. “We need policies that protect youth while ensuring adult smokers have access to evidence-based cessation tools.”
Future Implications and Next Steps
The study’s authors stress that further research is needed to understand the long-term health impacts of these genetic changes. They also urge policymakers to prioritize transparency in e-cigarette manufacturing and marketing. “Consumers deserve clear information about the risks associated with different products,” said Besaratinia. “This requires collaboration between scientists, regulators, and industry stakeholders.”
Dr. George emphasized that the study’s findings should prompt immediate action from health authorities. “We are not suggesting that vaping is risk-free for adults trying to quit smoking, but the genetic data shows that flavored products pose additional, unquantified risks,” she said. The team is now working on a follow-up study to assess whether these genetic changes are reversible after cessation.
As the vaping market continues to evolve, the study serves as a critical reminder of the potential health risks tied to product design and flavoring. With over 3,000 genes affected, the findings underscore the need for a nuanced approach to regulation—one that addresses both the immediate and long-term consequences of vaping. Public health experts recommend that individuals considering vaping consult with healthcare providers to weigh the risks against potential benefits, particularly for those attempting to quit traditional cigarettes.
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