American officials who are freaking out about the rising popularity of electronic cigarettes, especially among teenagers, generally fail to distinguish between experimentation and regular use. In fact, as Boston University public health professor Michael Siegel points out, surveys sponsored by the U.S. Centers for Disease Control and Prevention (CDC) do not even ask about frequency of use beyond once or more in the previous month. Two recent studies highlight the importance of inquiring further, showing that very few nonsmokers who have tried e-cigarettes are regular users.

One study, which Siegel discussed on his blog last Friday, analyzed data from the Youth Tobacco Policy Survey, which is sponsored by Cancer Research UK. The survey of 1,200 British 11-to-16-year-olds found that 12 percent reported trying e-cigarettes but only 2 percent reported using them more often than once a month, while just 1 percent reported using them more often than once a week. Furthermore, "regular e-cigarette use was found only in children who also smoked tobacco," belying CDC Director Tom Frieden's warnings that such products are luring teenagers who have never used tobacco into nicotine habits that might ultimately lead to smoking.

One of the researchers, Linda Bauld, a professor of health policy at the University of Stirling, explains the significance of these results, which are scheduled to be published in the journal Nicotine and Tobacco Research:

There's a common perception that the rise we've seen in the use of electronic cigarettes will lead to a new generation of adults who have never smoked but are dependent on nicotine. This fear is based on the expectation that due to the appeal of the products, children who have never used tobacco will be attracted to e-cigarettes and start to use them regularly. Our survey is in line with others in the different parts of the UK that show this is not happening. Young people are certainly experimenting with e-cigarettes, some of which do contain nicotine. However, our data show that at the moment this experimentation is not translating into regular use.

Another study, reported in the journal Tobacco Control last week, found that the fears of e-cigarette critics are not materializing among adults either. In a 2014 survey of 9,300 adults in Minnesota, 18 percent had tried e-cigarettes but most had not used them in the previous 30 days. Almost all of the past-month vapers (99 percent) were also smokers. Of the nonsmokers who reported vaping in the previous month, nine out of 10 did so infrequently, defined as vaping on five or fewer days.

The survey also asked about reasons for using e-cigarettes, including "to quit other tobacco products," "to cut down on other tobacco products," "because they might be less harmful than other tobacco products," "to use them in places where other tobacco products are not allowed," "owing to curiosity about e-cigarettes," "because they are available in menthol flavour," and "because they are available in flavours other than menthol." The first four reasons were classified as "goal-oriented." Not surprisingly, there was an association between vaping frequency and motivation:

Defining e-cigarette current use prevalence as any use in the past 30?days failed to differentiate a cluster of infrequent users at the low end of the distribution from other users. In addition to having a distinctly different behavioural profile in terms of use frequency, infrequent users were more likely to report curiosity as a reason for using e-cigarettes and less likely to report goal-oriented reasons, compared to intermediate or daily users. These results suggest that many infrequent users are experimenters, unlikely to continue their e-cigarette use over time. If that is the case, then measuring e-cigarette current use prevalence based on any use in the past 30?days may lead to an overestimate of regular users. That conclusion is reinforced by the finding that most individuals who had ever used e-cigarettes reported no use in the past 30?days.

These results, together with the awkward fact that smoking by teenagers continues to fall as vaping rises, reinforce the impression that public health officials and anti-smoking activists are grasping at straws to justify their knee-jerk animosity toward e-cigarettes. Instead of harping on unfounded fears that vaping will lead to nicotine addiction and an increase in smoking, they should be investigating the lifesaving potential of e-cigarettes, a far less hazardous alternative to the conventional kind.

[Thanks to Mark Sletten for the Tobacco Control link.]