Smoke without fire: What's the truth on e-cigarettes?

New Scientist, 30 October 2014

They've been called safe, dangerous, a way to quit smoking – and a way to start. Catherine de Lange sifts through the evidence about e-cigarettes

THE juice bar is clean and bright with a nice-looking selection of drinks and cakes – just like a regular London cafe, but with one big difference: the kind of juice that's on offer.

This is one of thousands of small outlets carving out a share of the growing e-cigarette market. Its main selling point is a vast array of flavoured nicotine liquids or e-juices. There are fruit flavours, minty flavours, fun flavours like cola and grown-up ones like rum, pina colada and even tobacco. After testing a few, I settle for watermelon and almond, plus a rechargeable electronic cigarette kit. And so my experiment begins.

E-cigarettes have been around for almost a decade, but in the past year or so have grown rapidly in popularity. And as their use has soared, the debate around their health effects has ignited.

On one side are those who view them as a godsend in the war on tobacco, because they offer smokers a safer way to feed their addiction and a crutch to help them quit. On the other side are those who argue that the devices might not be safe, that they won't help people give up smoking, or, worse, that they could reverse the gains of the anti-smoking movement.

As someone who has repeatedly fallen off the no-smoking wagon, I was interested to know whether arming myself with an e-cigarette could keep me from slipping back into unhealthy habits. But first I needed to find out how much we really know about the impacts of e-cigarettes.

The claim that e-cigarettes are a healthier alternative to smoking makes a lot of sense. Instead of hot, dirty smoke, you inhale cool, clean vapour – and hence avoid the toxins, carcinogens and particulates that are responsible for tobacco's toll on health.

"Smokers smoke for nicotine but they don't die from nicotine, they die from the combustion products in smoke," says Konstantinos Farsalinos, a leading e-cigarette researcher at the Onassis Cardiac Surgery Center in Athens, Greece. "If you compare tobacco cigarettes with e-cigarettes the difference in the risk is vast. For a smoker who switches, there is no doubt that there will be significant health benefits."

Even outspoken critics of e-cigarettes agree they are likely to be orders of magnitude safer than smoking cigarettes. "They have to be less toxic," says Stanton Glantz of the University of California, San Francisco.

That certainly chimed with my experience. After a couple of months, I found I was vaping more than I ever smoked, but it felt like no big deal. I found it relaxing, and except for a bit of a sore throat at first there were no noticeable negative effects – and no smell.

That, however, doesn't mean vaping is a breath of fresh air. I may not be breathing in smoke but I am still inhaling nicotine, flavourings, the solvents in which they are dissolved and numerous by-products, many of which are also found in tobacco smoke.

So far, though, the risks appear small compared with cigarette smoke – at least in the short term. Nicotine itself appears harmless, though addictive. The solvents are classed as safe and the nasties are found in trace amounts.

"We have strong arguments that e-cigarettes are less harmful," says Maciej Goniewicz, an oncologist at Roswell Park Cancer Institute in Buffalo, New York. "But are they really safe? What would happen after 20 years of puffing on e-cigarettes? We need the studies on this."

Unsurprisingly, given vaping's short history, such studies don't exist. But from what we know it seems unlikely that in 20 or 30 years we will face an epidemic of e-cigarette-related diseases.

A much more contentious – and important – question is whether e-cigarettes help people quit smoking. Despite anecdotal reports that they do, the evidence is as hazy as a puff of smoke.

Part of the problem is that e-cigarettes are so varied and evolve so fast. Although trials have found e-cigarettes to be as effective as nicotine patches at helping people quit, the results remain inconclusive, says Robert West of University College London. This is mainly because in the time it takes to conduct a clinical trial, the e-cigarettes used in it are already obsolete.

In possibly the most compelling study so far, West collected data on more than 5800 smokers who had tried to quit at some point in the previous six months using various strategies including e-cigarettes. He found that about 20 per cent of the vapers were successful. That was about twice the success rate of those who went cold turkey, roughly the same as those who used prescription drugs or nicotine replacement therapy, but lower than the success rate for "stop smoking" services.