One of the most challenging patient encounters for any family doctor is a discussion with long term smokers about quitting. Not because we don’t realize how bad smoking is — of course both doctor and patient know it’s a deadly habit. But it truly is very difficult to quit, no matter what we doctors say or offer. We try this and that, and patients quit and often restart, and the cycle of addiction continues. That’s why any new treatment that can really help the world’s smokers — who include more than half of all men in China – to quit smoking would be a medical miracle.

Enter the electronic cigarette, the battery-powered contraption that allows people to smoke tobacco-free, by vaporizing liquid nicotine and other additives. Though they still account for just a tiny sliver of the market in most countries, e-cigarettes have begun to explode in popularity over the last couple of years, including in China, where the vast majority of e-cigarettes are assembled. The controversy surrounding the product has erupted in turn. Are they a miracle, or a mirage? Any casual reader of the news knows that there’s a massive worldwide debate among doctors and public health experts regarding e-cigarettes. Many experts argue passionately they should be made available to all. Others say that the potential health risks have yet to be fully understood and that they should be treated just like a regular cigarette, to be regulated or even banned pending further study. I stand in the pro-e-cigarette corner — for now, at least — provided the production, distribution and marketing of the product is properly monitored and regulated.

The first job of a doctor is to “do no harm”, and can we reliably say that electronic cigarettes do no harm? There is far from a medical consensus on this, and the World Health Organization finally added their input just this month in their new report, calling electronic cigarettes an “evolving frontier filled with promise and threat for tobacco control.” They find “currently insufficient evidence to conclude that e-cigarettes help users quit smoking or not.” They also strongly urge regulations to protect children, including severe restrictions on advertising as well as any flavoring or packaging which is proven to be attractive to children.

I do agree that e-cigarettes do present some potentially serious reasons for concern. Children can accidentally drink the nicotine liquid they contain, causing serious stomach problems, even though responsible parents already know that any potentially harmful chemicals should always be locked away from children. I’m also worried that more and more teenagers are starting to think that e-cigarettes are cool, especially based on the advertising. More than 260,000 American youths who had never smoked a cigarette before tried e-cigarettes in 2013, according to a U.S. Centers for Disease Control and Prevention study published in August, up more than three-fold from about 79,000 in 2011. But a reassuring new survey from the UK’s public health charity Action on Smoking and Health (ASH) shows that the vast majority of children trying e-cigerettes also are smoking regular cigarettes, and 98% of children who have never smoked at all have still never tried an electronic cigarette.

Many critics of e-cigarettes have focused on this potential problem with children, but the fact remains that right now, tens of millions of chronic smokers worldwide are at great immediate risk of health problems. Here in my family medicine practice, when I have a patient in front of me with a 30-year history of smoking a pack a day, I am acutely aware that this person has just crossed a very dangerous medical milestone. Such 30-pack-year smokers have such a greater risk for cancers, heart disease and all-cause mortality that the US Preventive Service Task Force now recommends that all such smokers get an annual chest CT to look for lung cancer . I have a professional and ethical obligation to try everything to save this person’s life, and I would recommend that they try any means possible to quit — including e-cigarettes.

The anti-e-cigarette crowd will often say that data on the health effects is poor, and it’s true that until recently there were few strongly designed studies. But now there are a couple of better studies called randomized controlled trials, and we should re-examine our previous stances based on this new, firmer evidence.

The first, called the ECLAT study, was published in the scientific journal PLOS ONE in early 2013. It followed 300 smokers in Italy for one year, giving them three months of different nicotine doses of e-cigarettes. None of these smokers initially were interested in quitting smoking. At the end of the twelve month study, 13% of the higher-dose group had quit, compared to 9% from the lower-dose group and 4% from the placebo group. Also, the great majority of quitters (73%) were no longer using their e-cigarettes, which I find a reassuring argument against those who fear that smokers will replace one addiction with another.

An even better research trial was the ASCEND study, published by the medical journal Lancet late last year, which finally gave us data comparing e-cigarettes to nicotine patches, a commonly used therapy to help people quit smoking. In this randomized controlled trial of 657 smokers in New Zealand, 7.3% of the e-cigarette users stopped smoking at 12 months, a better result than the 5.8% in the nicotine patch group (and 4% in the placebo group). Nicotine patches are notoriously unhelpful for most of my patients, and this study suggests that e-cigarettes may be more useful than patches, which should be welcome news to all doctors on the front lines of this battle against smoking.

Besides those two trials, a few review articles published in these last few months also add much needed intellectual weight to this important debate. One review just published last July in the medical journal Addiction concluded that e-cigarettes “are likely to be much less, if at all, harmful to users or bystanders” than cigarettes. Another systematic review just published last March concluded that, “electronic cigarettes are by far a less harmful alternative to smoking and significant health benefits are expected in smokers who switch from tobacco to electronic cigarettes.”

In terms of public health impact, I generally agree with the recent comments from the European Journal of Public Health, stating in an editorial that ” it is simply too early to know” exactly how effective or safe are e-cigarettes. But they also stress in a quote: “As nicotine addiction expert Professor Michael Russell wrote in 1976, ‘people smoke for the nicotine but they die from the tar’. E-cigarettes deliver the nicotine without the tar, as their use involves no combustion. Common sense therefore dictates that e-cigarettes are significantly less harmful than cigarettes, and for the individual smoker who cannot or does not want to quit, there is little doubt that switching to e-cigarettes will be beneficial.”

If we limited use of e-cigarettes only to smokers trying to quit, then we could probably save many of the six million annual deaths worldwide from smoking. However, I am very uncomfortable with e-cigarette companies’ aggressive marketing campaigns on TV and other mass media, often targeted to youth, trying to make them hip and cool. It brings to mind the infamous Joe Cool advertising campaign from 1987-97 which attracted many new smokers to the Camel brand, and made Joe Camel as recognizable as Mickey Mouse among six year old children. If a certain percentage of people who never considered smoking suddenly try an e-cigarette and then move on to real cigarettes (the “gateway drug” theory), then the long-term risks could outweigh the benefits.

Because of this, I do think that governmental health authorities should regulate the marketing as well as availability of e-cigarettes, particularly as it concerns minors. I think they should be locked up right next to the nicotine patches on the shelves in all pharmacies, with proof of age over 18 required to purchase them. And I certainly think almost all types of advertising should be banned, as well as limits on the kid-friendly flavoring and coloring. But I don’t think regulation should go overboard, by requiring a prescription for it, for instance. I also feel it’s counterproductive to ban e-cigarette use in all public places, but perhaps for now such bans aren’t totally unreasonable, as we wait clearer data on risks.

I should disclose here that I am an occasional fan of smoking mini-cigars, and last year I bought an electronic pipe for myself, mostly to satisfy my craving for the nicotine rush without reaching for a real cigar. So I can personally empathize with a smoker’s addiction, and I understand firsthand why e-cigarettes can be successful in a way that a nicotine patch will never be: they still allow you that habitual sensation of smoking — holding, puffing, seeing the smoke — without nearly the same severe health risks to yourself and to others nearby.

Some people argue that you’re replacing one addiction with another, and I have two things to say to that: first, the trial above proves that only a small percentage of quitters continue to use e-cigarettes. Second, and more importantly: I would much rather have any smoker hooked on nicotine via an e-cigarette than from continuing to burn tobacco. Again, I can’t stress this enough: nicotine itself does not cause cancer or any chronic lung or heart disease. ‘People smoke for the nicotine but they die from the tar’, as Dr. Russell said four decades ago.

Let’s go back to my title, “can an e-cigarette save your life?” If you’re a smoker for many decades and you now switched completely to e-cigarettes, then yes, you may have just saved your life. If only 10% of all smokers in China switched to e-cigarettes, that could save countless thousands of lives every year.

If a series of new studies comes along that proves that long term risks actually are worse than benefits, then I will reassess my position. But for now, I will continue to endorse this therapy to my patients. I believe it would be unethical not to.

Chinese translation of this article is available in my health column in the New York Times China edition