A modeling study by top tobacco control experts finds that e-cigarettes are likely to provide public health benefits based on “conservative estimates” of the likely uptake of vaping and smoking by adolescents and young adults.

The study, published in Nicotine & Tobacco Research, suggests that “recent claims by some scientists that e-cigarettes are likely to act as a gateway to the use of tobacco products are overstated,” says the study’s lead author, population scientist David Levy, PhD, a professor of oncology at Georgetown Lombardi Comprehensive Cancer Center.

If used instead of smoking, e-cigarettes provide the potential to reduce harm and improve public health, Levy says. But they also have the potential to increase harm if youth who would not have otherwise smoked become cigarette smokers as a direct consequence of first trying e-cigarettes— the so-called “gateway” hypothesis that has gained favor by some, he says.

“Our study indicates that, considering a broad range of reasonable scenarios, e-cigarettes are likely to reduce cigarette smoking and not lead to offsetting increases in harm from the use of e-cigarettes and more deadly cigarettes,” Levy says. “When we consider the plausible positive and negative aspects of e-cigarette use, we find that vaping is likely to have a net positive public health impact.”

The team that developed the model — researchers from the US, Australia and Canada — projected a reduction of 21% in smoking-attributable deaths and 20% in life years lost as a result of use of e-cigarettes in people born in 1997 or after, compared to what would have happened if e-cigarettes were not an option.

“Our model is consistent with recent evidence that, while e-cigarette use has markedly increased, cigarette smoking among youth and young adults has fallen dramatically,” Levy says.

Levy supports the recent decision by the US FDA to ban use of e-cigarettes to youth younger than 18 “because we still want to discourage use of all nicotine and cigarette products,” he says.

Levy also says that, despite their estimates of an overall public health benefit from e-cigarettes, youth use of these products needs to be continuously monitored, since use patterns are likely to change as the product and awareness about the product changes.

While supporting prudent FDA regulation of e-cigarettes, Levy says he is concerned that regulating e-cigarettes in the same manner as cigarettes will pose a burden to smaller companies who will not have the resources necessary to gain marketing approval for their products. “Overregulation of e-cigarettes might actually stifle the development and marketing of safer products that could more effectively displace cigarettes,” he says.

Co-authors of the study are David Abrams, PhD, Zhe Yuan, MS, and Yian Zhang, MS, from Georgetown Lombardi Comprehensive Cancer Center; Andrea C. Villanti, PhD, MPH and Raymond Niaura, PhD, from the Schroeder Institute for Tobacco Research and Policy Studies at Truth Initiative; Ron Borland, PhD, from Cancer Control, Victoria, Australia; Rafael Meza, PhD, from the University of Michigan; Theodore R. Holford, PhD, from Yale University, Geoffrey T. Fong, PhD, from the University of Waterloo and the Ontario Institute for Cancer Research, Canada; and K. Michael Cummings, PhD, MPH, from the Medical University of South Carolina.

The study was funded by the National Institute on Drug Abuse (R01DA036497), the National Cancer Institute (P01- CA200512) and the Cancer Intervention and Surveillance Modeling Network (UO1-CA97450).

Cummings has received grant funding from the Pfizer, Inc., to study the impact of a hospital-based tobacco cessation intervention, and has received funding as an expert witness in litigation filed against the tobacco industry. The other co-authors report no related financial interests.