But despite their widespread use, these devices have arrived so quickly that the evidence on how safe they are, and how effective they are at helping people quit smoking, is still in its relative infancy.
And from a glance at the news, it would be easy to believe that this evidence is swinging from one side to the other every few weeks.
From our perspective, however, the reality is far more stable. And we think it’s important to demystify the situation, because of the potential for harm, confusion and lost opportunity.
But we thought we’d take a look at some of the rather controversial e-cigarette headlines that have appeared this year.
There are a variety of devices on the market collectively called ‘e-cigarettes’.
And although they differ in shape, size and mechanism – from first generation ‘cig-a-likes’ to later generation ‘tank-style’ devices – they all work in a similar way: they use an electric current to heat and vaporise a liquid form of nicotine to produce a vapour that’s inhaled to give a hit of nicotine.
This is very different to traditional tobacco cigarettes, which burn tobacco leaves producing a dangerous cocktail of carcinogens in addition to nicotine.
So, e-cigarettes should, in theory, be far safer than tobacco products – and they almost certainly are.
But you wouldn’t necessarily think so from recent media reports.
New Year, new rumours
In January, the Daily Mail ran the misleading headline that “Some e-cigarettes may release more cancer-causing chemicals than regular tobacco”. After we spotted it, it was updated to “Some e-cigarettes may release more of a cancer-causing chemical than regular tobacco, study suggests” [emphasis ours].
But this still over-exaggerates the news in our opinion.
The study behind the headlines looked at levels of chemicals that release formaldehyde – a known carcinogen – in vapour from a ‘tank-style’ e-cigarette when run at different voltages.
It found that, at a high voltage, daily use of the e-cigarette could release more formaldehyde than smoking 20 cigarettes.
But if we look a bit more closely at the research, there are several reasons why we don’t think this warranted the headlines it got.
Firstly rather than measuring the chemicals that users are actually exposed to, the study used a machine to generate and measure the e-cigarette vapour.
This is particularly important in this case, because at the lower voltage tested, no formaldehyde was found. So the results entirely depend on how these products are used.
It’s also important to note that this was only looking at one type of e-cigarette, and this can’t necessarily be generalised to the extensive range of products out there. This is one of the key limitations with the evidence around e-cigarettes, and why we need to take a balanced view of all the information we have – rather than relying on one study.
Furthermore, the study in question only looked at one chemical so it can’t be used to compare the overall level of risk.
A follow-up study was published this week, exploring the conditions under which aldehydes (including formaldehyde) may be generated. While this addresses some of the concerns we outlined here, it doesn’t change our overall view on the safety of e-cigarettes.
So what do other studies say? According to a review of evidence commissioned by Public Health England last year, when looking at the vapour from e-cigarettes as a whole, there seems to be far fewer chemicals present than in tobacco smoke, and mostly at much lower levels.