Smokers should be encouraged to try e-cigarettes to help them quit, according to a review from Britain's top public health body that is the latest salvo in the increasingly politicised debate over e-cigarettes.
Australia's top smoking experts have rejected the report, saying it displays "naive optimism" and is based on flawed research. They say the proponents of so-called "vaping" are treating e-cigarettes as if they are more beneficial than other quit-smoking treatments despite little evidence they are, and some evidence they could even be worse.
The debate over e-cigarettes has become so bitter in part because of the high stakes. Tobacco is an incredibly dangerous drug – it kills half of all people who use it. Most experts are pretty clear e-cigarettes are not going to be anywhere near as dangerous as that.
But whether or not e-cigarettes are an important tool to help people quit, and whether they should face the same requirements as other quit-smoking drugs to prove their safety and efficacy, is where it starts getting messy.
Add to that vociferous promotion from marketers and a community of online devotees, and you have the makings of an internet firestorm. Oh, and there's also that issue of Big Tobacco buying up independent e-cigarette companies. According to the American Heart Association, 10 years from now the three top tobacco companies are expected to share 75 per cent of the profits from sales of e-cigarettes.
The expert review from Public Health England says the nicotine-delivery devices are basically safe, and lead to good quit rates.
But it is concerned that the debate is leading some smokers to think e-cigarettes are just as dangerous as normal cigarettes.
It found the "best estimate" is that e-cigarettes are around 95 per cent less harmful than smoking.
Ann McNeill, a professor at King's College London and author of the review, said e-cigarettes had the potential to be a game-changer in public health.
"In my view, smokers should try vaping and vapers should stop smoking entirely," she said.
But Cancer Council NSW manager of tobacco control Scott Walsberger said the research was flawed, with the data not supporting some of the positive statements about e-cigarettes.
He said it was not clear all ex-smokers who used e-cigarettes had used them to quit, and since all e-cigarettes contained different ingredients and levels of nicotine, it could be misleading to attach a definitive figure like "95 per cent less harmful" to them.
And while the report stated children who never smoked were not using e-cigarettes, Cancer Council research had found nearly a quarter of people aged 18 to 24 in NSW had tried them.
"And it showed people were using them for novelty value, or because their friends were, rather than to quit smoking, so for us that is concerning," he said.
And he was concerned that many people use e-cigarettes to supplement or slightly reduce their smoking.
"We don't promote a harm-reduction approach and we don't promote just cutting back on the number of cigarettes because … we know that doesn't change your overall risk of developing cancer," he said.
He said if e-cigarettes are beneficial for people wanting to quit, then they should be tested and regulated in the same way as things like nicotine patches.
University of Sydney professor of public health Simon Chapman agreed that while e-cigarettes were less toxic than normal cigarettes, that was not much help if you are using them alongside your normal cigarettes.
"The success rates of helping people to quit smoking using e-cigarettes are largely overhyped in my opinion," he said. "[Tobacco companies] have lots of interest in getting people to quit smoking, they want people to use both products, as is happening already.
"I just despair at the naive optimism of some of these [researchers]."
He said a study in the journal Addiction had recently found very few e-cigarette users actually quit smoking after a year, with even the best results showing more than 70 per cent did not quit.
