Public health benefits of e-cigarette use tend to outweigh the harms

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 U.S., Australia and Canada -- projected a reduction of 21 percent in smoking-attributable deaths and 20 percent 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 U.S. Food and Drug Administration 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.