A new study published online ahead of print in the journal Nicotine & Tobacco Research pretty much blows out of the water the hypothesis that youth e-cigarette experimentation causes kids to progress to cigarette smoking.
(See: Villanti AC, et al. Frequency of youth e-cigarette and tobacco use patterns in the U.S.: Measurement precision is critical to inform public health. Nicotine & Tobacco Research. Published online on December 24, 2016.)
The study is novel because unlike similar research reported by the Centers for Disease Control and Prevention, this one doesn't just analyze current e-cigarette use (any use in the past 30 days) but quantifies the frequency of use (number of days used in the past 30 days). In addition, he breaks down e-cigarette use at each frequency level by concomitant tobacco product usage.
The main finding of the paper is that only 0.1% of all middle- and high-school students are nonsmoking, frequent e-cigarette users (defined as those who have vaped at least 10 days of the past 30 days):
"It was rare that tobacco naive youth reported using e-cigarettes and if they did, rarer still to find them using them frequently (i.e., fewer than 0.1% used on 10 or more days per month)."
The paper criticizes all previous studies which have been cited by anti-tobacco advocates as demonstrating that e-cigarettes are a gateway to smoking for: (1) not adequately measuring the frequency of e-cigarette use and classifying youth as vapers even if they use e-cigarettes only one or twice a month; and (2) not adequately accounting for dual use of e-cigarettes and tobacco products.
The authors conclude with an admonition to tobacco control researchers: "When interpreting findings for purposes of tobacco control strategy and policymaking, care must be taken to avoid biases, confounding, over or underestimates of trajectories and interpretations of results that go beyond the limitations of the data."
The Rest of the Story
This study casts serious doubt on the claims of many anti-tobacco advocates and groups that e-cigarettes cause youth to initiate smoking. Based on the findings of this research, it is extremely rare to find nonsmoking youth who experiment with e-cigarettes and then go on to become regular vapers. It appears that most e-cigarette use among nonsmokers is infrequent and experimental, reflecting the likelihood that vaping among nonsmokers remains a purely social phenomenon without any addictive component. This makes it implausible that e-cigarettes represent a gateway to youth smoking. Further research from longitudinal studies is necessary to confirm this finding, but for now, there is no reason to believe that e-cigarette use increases the use of tobacco among adolescents.