“Arguments about electronic cigarettes (e-cigarettes) and what do about them rumble on. I won’t wade into the broader debate, but I direct you to a recent viewpoint article (McKee and Capewell, 2015), and accompanying commentaries (particularly McNeill et al., 2015).
The main arguments involve the safety of e-cigarettes (relative to smoking regular cigarettes and relative to, well, breathing air), their effect on renormalisation of tobacco smoking when its prevalence is declining, their role as smoking cessation aids, and their use by young people.
The present article is related to the latter issue, specifically the worrying possibility that use of e-cigarettes by young people may make them more likely to progress to smoking regular cigarettes in the future.
Last year I wrote about a cross-sectional study which showed that American youth who used e-cigarettes were more likely to smoke regular cigarettes and less likely to quit smoking than others who did not use e-cigarettes (Field, 2014). This study caused quite a stink at the time, largely because it was interpreted as evidence for the claim that e-cigarettes may be a ‘gateway’ into 
tobacco smoking for young people, although various commentators were quick to point out that the findings didn’t imply that at all. A subsequent longitudinal study (Leventhal et al., 2015) demonstrated that use of e-cigarettes among American high school students was associated with subsequent progression to use of regular cigarettes, although the authors of that study emphasised that this does not mean that e-cigarettes play a causal role…”
Read the rest of Matt’s blog @ The Mental Elf Service
References:
Field M. (2014) E-cigarettes and youth: are e-cigs encouraging more use of conventional cigarettes? The Mental Elf, 2 Oct 2014.
McKee M, Capewell S. (2015). Evidence about electronic cigarettes: a foundation built on rock or sand?BMJ, dx.doi.org/10.1136/bmj.h4863
McNeill A, Brose LS, Calder R, Hitchman SC, Hajek P, McRobbie H. (2015). Evidence about e-cigarettes: They are much safer than cigarettes and do not lure children to smoking. BMJ
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