Just one day after the US National Institutes of Health reported that students who have used electronic cigarettes by the time they start ninth grade are more likely than others to start smoking traditional cigarettes and other combustible tobacco products, an expert independent evidence review published Wednesday by Public Health England (PHE) concludes that e-cigarettes are significantly less harmful to health than tobacco and have the potential to help smokers quit smoking.
Key findings of the review include:
- the current best estimate is that e-cigarettes are around 95% less harmful than smoking
- nearly half the population (44.8%) don’t realise e-cigarettes are much less harmful than smoking
- there is no evidence so far that e-cigarettes are acting as a route into smoking for children or non-smokers

Image/Jakemaheu at the wikipedia project
The review, commissioned by PHE and led by Professor Ann McNeill (King’s College London) and Professor Peter Hajek (Queen Mary University of London), suggests that e-cigarettes may be contributing to falling smoking rates among adults and young people. Following the review PHE has published a paper on the implications of the evidence for policy and practice.
The comprehensive review of the evidence finds that almost all of the 2.6 million adults using e-cigarettes in Great Britain are current or ex-smokers, most of whom are using the devices to help them quit smoking or to prevent them going back to cigarettes. It also provides reassurance that very few adults and young people who have never smoked are becoming regular e-cigarette users (less than 1% in each group).
However, the review raises concerns that increasing numbers of people think e-cigarettes are equally or more harmful than smoking (22.1% in 2015, up from 8.1% in 2013: ASH Smokefree GB survey) or don’t know (22.7% in 2015, ASH Smokefree GB survey).
Despite this trend all current evidence finds that e-cigarettes carry a fraction of the risk of smoking.
Emerging evidence suggests some of the highest successful quit rates are now seen among smokers who use an e-cigarette and also receive additional support from their local stop smoking services.
Professor Kevin Fenton, Director of Health and Wellbeing at Public Health England said:
Smoking remains England’s number one killer and the best thing a smoker can do is to quit completely, now and forever.
E-cigarettes are not completely risk free but when compared to smoking, evidence shows they carry just a fraction of the harm. The problem is people increasingly think they are at least as harmful and this may be keeping millions of smokers from quitting. Local stop smoking services should look to support e-cigarette users in their journey to quitting completely.
Professor Ann McNeill, King’s College London and independent author of the review, said:
There is no evidence that e-cigarettes are undermining England’s falling smoking rates. Instead the evidence consistently finds that e-cigarettes are another tool for stopping smoking and in my view smokers should try vaping and vapers should stop smoking entirely.
E-cigarettes could be a game changer in public health in particular by reducing the enormous health inequalities caused by smoking.
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