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Although they were almost unheard of a few years ago, there are now an estimated 2.1 million e-cigarette users – or vapers – in the UK.

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.

We’ve blogged before about the promises and challenges for these products.

But we thought we’d take a look at some of the rather controversial e-cigarette headlines that have appeared this year.

Quick recap

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.

Update 21/05/15: 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.

Are you a man or a mouse?

Misleading headlines

Misleading headlines

Last week e-cigarette research hit the headlines again with “E-cigarettes are ‘not a safe alternative’” and “E-cigarettes ‘increase the risk of flu and pneumonia’”. And the most misleading, and in this case inaccurate, of all –as the image on the right from the Metro shows – “’Cancer threat’ in e-cigarette vapour”. (The use of speech marks in these headlines – or ‘scare quotes’ as they’re often referred to in journalism circles – is the first indication that all may not be as it seems.)

Taking a closer look at why some of these headlines are misleading, the study explored the impact of e-cigarette vapour on a small number of mice, and found they were more susceptible to infections.

The comparison made here was only against mice who breathed air – so it’s impossible to draw conclusions about how this stacks up against exposure to cigarette smoke.

On top of this, there are a number of other limitations to this study, the first of which is that it’s always questionable how far results of studies in mice can be applied to humans. The mice were exposed to a dose of e-cigarette vapour to match the levels of use by humans, rather than being scaled down.

And again, this study used a machine-generated dose of vapour from an e-cigarette. And there was certainly no attempt to look at cancer risk as part of this study.

So – taking these caveats into account – this study is definitely helpful in terms of opening up another avenue for exploring the potential health impact of e-cigarettes. And it underlines the need for long-term follow-up of users.

But to draw actual conclusions about how ‘safe’ e-cigarettes are, you need studies looking at the impact of e-cigarettes on human users.

Are there any such studies? There hasn’t been time yet to see any long-term health impact e-cigarettes, but in the short-term, a 2014 meta-analysis found that the most common health complaints seem to be irritation, nausea, headache and dry cough. And overall these negative effects seem to be less compared to smoking cigarettes.

The results of the small studies looking into the immediate impact of e-cigarette use have been inconsistent, so at this stage we don’t know if there will be a significant positive or negative impact on lung function compared to cigarettes. We know cigarettes hugely increase the risk of pneumonia and other respiratory problems.

We are keen to understand the impact of e-cigarettes, and this is why we are investing into e-cigarette research to understand better the risks of using e-cigarettes and what impact they have on smoking rates.

What we know for now

Overall, the evidence so far (including the studies discussed here) suggests that e-cigarettes are almost certainly far safer than smoking tobacco. But note the use of the word “safer” rather than “safe” – they are not entirely risk-free products and shouldn’t be used by non-smokers or people under 18.

But here’s what we do know: it’s hard to overstate the impact of smoking on your body – quitting is the most important thing you can do for your health. While the evidence for e-cigarettes builds, there are more established, proven quitting methods that boost your chances more than e-cigarettes seem to. But we do recognise their potential to help some people stop smoking.

Commenting on the evidence as is stands, Professor Linda Bauld, a Cancer Research UK expert on cancer prevention, said: “As smoking remains the biggest preventable cause of cancer we need to do all we can to continue to reduce smoking rates. Confusion over e-cigarettes, often driven by misleading headlines, may be hindering rather than helping more people move away from tobacco.

“These products have real potential but we need to conduct and correctly interpret new research to keep giving people accurate information about the choices available to them.”

So we imagine e-cigarettes will continue to live up to their polarising reputation for some time yet.

But when it comes to robust scientific evidence, it will take time – and slow and steady wins the race.

Nikki Smith is a senior health information officer at Cancer Research UK



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Brian April 21, 2015

I am an ex cigarette smoker. I made the change to refill e- cig to see if I felt healthier. Not to give up smoking. Now been smoking e- cig for 3 months. Benefits so far breathing better, food tastes better, sense of smell better. So thumbs up from me. I am now turning 50 years of age. Had smoked cigarettes from the age of 13 years old. Always been active in work & play, so consider my self quite fit for a smoker. Now feel even better. No ill affects to report. Feel happier that I’m feeling healthier & save lots of money in the bargain. I’m guessing all of the scare mongering is down to loss of revenue. I agree they should only be sold to 18s & above, as they are addictive. So some controls are needed. But banning them in public places is extreme as I believe we breath more toxic fumes from traffic pollution than we do from trace elements that are exhaled from e-cigs. I Used to live in a town with heavy traffic congestion, always coughed & hacked in the mornings. Which I put down to being a long term smoker of cigarettes. Moved too a small village with no traffic congestion. Coughing stopped within 2 months of moving to my new home. “Still smoked”. But lungs felt better. So my concerns as a parent, what have I been letting my children breath into their lungs, while living in a congested area.
When I was at school there was a lot less traffic & can only remember 2 cases of asthma at my school of 1000 pupils. Would like to see what the figures are now in a built up area. Maybe this is a different argument so will stop now. But I think it’s all relevant.
Good health to you all.

Paul February 13, 2015

As this post highlights, there has been a lot of disinformation in the media surrounding the humble electronic cigarette. As the studies are completed, and results published the amount of positive outcomes are beginning to be shown.

This post from CR_UK shows that with the right balanced approach, taking in all the scientific studies; the electronic cigarette can be a very useful tool as both an alternative to smoking and a useful method in cessation.

Dodderer February 13, 2015

I think the problem that Tobacco Control has with ecigs is that the reality has preceded the ‘research’.Being a bit of a cynic,I have observed academics proposing new policies,researching their effectiveness,lobbying government and then assessing the results.

Those opposing ecigs have tried the same tactics but have been met by a real world storm of user evidence and their critical appraisal of the dishonest research.

I welcome your acceptance of reality – it will save lives

Pixeljuice February 13, 2015

This article is going viral… So get ready Nikki :D

Pixeljuice February 13, 2015

Thank you for this well written, well thought out, and honest piece.. I’m so glad that Cancer Research are now coming around to the fact that vaping is not the evil that the press have it as. I’m also glad that you guys are looking at the facts, more than you were a year or so ago… For that I salute you.

Frances Maynard February 13, 2015

I quit smoking and changed to vaping 15 months ago , my health has improved considerably and i have saved thousands of pounds and im now on zero nicotine since xmas theres no going back for me.
I had tried everything from tablets, patches, acupuncture and 9 visits to the hypnotist but nothing worked , i was on 50-60 per day but E cigs worked for me straight away.
Even if there is a slight risk its 100 times safer than cigarettes.

Dan February 13, 2015

Last time I commented on a CRUK blog it was to admonish the shortsighted and misinformed info you were spreading about ecigs.

I am so impressed that you have been keeping up with the research and adjusting your view to fit. What’s more seeing through the badly designed and sometimes deliberately biased ‘studies’.

I applaud this wholeheartedly, and though I still think you might be being slightly over cautious with the muted support, I understand why this is and am sure as more research is released you will become more supportive.

Seriously, High-five CRUK!

Richard Bird February 12, 2015

About time you opened your eyes, and yes there is light at the end of the tunnel. Its from an LED not a cigarette butt.
This could end tobacco smoking for ever, IF the “public health” brigade don’t screw it up.

Ray L. February 12, 2015

It pleases me to read good rational digest about vaping. I have used advanced vape devices for more than a year following a 27 year smoking habit. I am also aware of many other people who have made the same switch, people i talk to daily over the internet. The one thing we all share in common is the health benefits of switching to vaping. We are all ‘non smokers’ now & fell much better for it. Further to that & speaking for myself, i very much enjoy my e liquid activity & can happily blow clouds of vapour daily without feeling any negative effect. I can run without being overly short of breath & i can cycle for sustained periods without tiring in the way i did as a smoker.
It’s great that CRUK are getting behind vaping in a realistic way because those of us existing vapers, those of us in the know are constantly screaming at the media for publishing untruths & scaremongering lies. Real studies of regular vapers will show that it is in fact a very real, viable & great alternative to smoking tobacco & i firmly believe that vaping has a fantastic future.

Bill Godshall February 12, 2015

Considering that CRUK has made many false and misleading fear mongering claims about vaping and e-cigs during the past several years (to lobby for MHRA and EU regulations that will, if implemented, protect cigarettes and threaten the lives of vapers and smokers by decimating the e-cig industry), this posting is refreshing to read.

But in fact, the growing mountain of scientific and empirical evidence has consistently found that e-cigarettes (aka vapor products):
– are 99% (+/-1%) less hazardous than cigarettes,
– have never been known to cause any disease,
– are virtually all (i.e. >99%) consumed by smokers and by exsmokers who switched to vaping,
– have replaced more than 3 Billion packs of cigarettes worldwide in the past five years,
– have helped several million smokers quit smoking, and have helped several million more sharply reduce their cigarette consumption,
– are more effective for smoking cessation than FDA/MHRA approved nicotine gums, lozenges and patches (which have a 95% failure rate),
– pose fewer risks than FDA/MHRA approved Verenicline (Chantix/Champix),
– have never been found to create nicotine dependence in any nonsmoker (youth or adult),
– have never been found to be a gateway to cigarette smoking for anyone,
– emit trace levels of nontoxic aerosol that poses no harm to nonusers,
– have never poisoned any human, and
– have further denormalized cigarette smoking (as youth and adult smoking rates and cigarette consumption have declined every year since 2007 when vapor sales began to skyrocket).

Vapers and smokers have a human right to be truthfully informed that vaping is far less hazardous than smoking cigarettes, and to have legal and affordable access to these lifesaving products.

Consistently, public health agencies, organizations and professionals have an ethical duty to truthfully inform vapers and smokers (and the public) that vaping is far less hazardous than smoking, and to ensure that lifesaving e-cigs remain legal and affordable alternatives for smokers.

Since public health has improved every time a smoker has vaped an e-cig instead smoking a cigarette, all real public health advocates strongly support smokers switching to far less hazardous vaping.

Although CRUK appears to be moving in the right direction, it still has to atone for its past actions to discourage smokers from switching to vaping, and by lobbying for regulations and laws that protect cigarette markets and threaten the lives of vapers and smokers.

Bill Godshall
Executive Director
Smokefree Pennsylvania
1926 Monongahela Avenue
Pittsburgh, PA 15218

RobW February 12, 2015

That’s a surprise, a reasonably positive article from CRUK, it wasn’t long ago when you were most definitely in the middle of the scaremongering crowd, so well done, although long overdue it’s a step in the right direction.

It would be very useful if you could raise the profile of the latest statistics, it’s tragic that fewer smokers are making the switch due to reckless scare stories, how many lives have been lost due to the actions of willing idiots and corporate financial interests.

The level of ignorance and ideological opposition however remains high amongst many in the public health sphere, this is the audience where CRUK could have a very significant influence. Don’t let this blog be an isolated article read by just a few, go out there and bang some PH heads together.

j kendall February 12, 2015

People will smoke or use a vapour e cig no matter what any one says. Leave them to it

Margaret Hermon February 12, 2015

What a pity this more reasonable approach has been so long in the making. The headlines you have quoted have probably driven thousands back to smoking – we only need half an excuse – not to mention those who have decided to not even try it “Because it’s just as bad as smoking”. This monstrously slanted publicity is spawned by sloppy if not deliberately bad research and someone is funding that. Most of us know WHO. If CRUK’s stance on this has really improved it would be good if they backed the opposition to the TPD as it stands, which amounts to handing the e-cig industry to the Tobacco and Pharmaceutical Multinationals on a plate. The obscene Press scare-stories occupy a whole page – the retractions an inch or two; these parasites have blood on their hands.

Mr Johnson February 12, 2015

I don’t need any evidence that they are indeed better for you than cigerettes, I’ve been vaping for almost three years now and I honestly can say I feel fantastic, I can now do a cardiovascular work out for over an our! Three years ago I couldn’t walk to the top of my stars without huffing and puffing! That’s all the proof I need to tell me I made the right choice to switch to vaping instead of smoking, I most certainly don’t need lab reports from a scientist that has no other interest in this other than to try and scaremonger folk that they are doing something more harmful than smoking!

Alan Beard February 12, 2015

A reasonably balanced appraisal from CRUK with the exception of using ‘proven quitting methods’
NRT has a dismal success rate and medications like Chantix have many safety questions . Three NHS Stop Smoking Services have embraced the use of e-cigs in smoking cessation attempts – the pioneer of this Louise Ross from Leicester SSS has reported very favourable results over the 12 months since introducing the policy.
Hertfordshire Public Health Director Jim McManus has also got the backing of elected councillors for introducing a similar e-cig friendly policy in his area.
These are very positive steps to realise that e-cigarettes are part of a solution not part of a problem. The questions may well remain regarding safety for many years, but for now as long as appreciably safer (95-99%) that should be more than adequate for now,

Sarah Jakes February 12, 2015

Thank you for this blog Nikki. In the last few weeks we have seen wave after wave of propaganda against e-cigarettes and whilst I’m sure the originators, and the media who sensationalise it, think it serves some scientific purpose, the main result seems to have been to dramatically reduce the number of smokers who believe that e-cigarettes are safer than smoking. It’s a tragic state of affairs and it’s good to see an authoritative source such as CRUK exploding some media myths.