Everybody’s got an opinion on e-cigarettes: ask ten people about their safety and you’ll get ten different answers. Fierce debates can rage because there just isn’t a lot of data yet, but there are a few things experts can agree on. Let’s look at the details.




Vaping is controversial because it’s new, which means two things. First, the science isn’t settled yet on how safe it is. And second—perhaps more importantly—political and commercial interests haven’t figured out yet where they stand. Does Big Tobacco see vaping as a competitor or a market opportunity? Is vaping a boon to public health or just a gateway cigarette?



With so many questions unsettled, we can’t give you a clear yes-or-no answer in a single Lifehacker post. (A lot of life’s questions can be answered that way, but not this one.) Instead, we’ll look at the evidence behind a couple of key questions, and tell you what the experts agree on and what is still up in the air.




Do E-Cigarettes Contain Harmful Ingredients?

Let’s start with the obvious: Nicotine is present in most e-cigarettes. That’s the whole point if you’re using it to replace a tobacco cigarette, or if you’re trying to quit. While fancy flavors of the added “juice” get a lot of press, convenience store sales are almost all flavorless or menthol-flavored nicotine delivery vehicles.



Nicotine is addictive, but it’s not carcinogenic. That leads e-cigarette advocates to make claims like “The problem with traditional cigarettes is the additives, smoke and chemicals, not so much the nicotine,” but that’s not true. Nicotine has plenty of problems of its own. It can mess with teenagers’ brains, and it’s still not safe for pregnant women: nicotine interferes with fetal development, including development of the lungs, and makes premature birth more likely.

The carcinogens are, instead, found in the tar component of cigarettes. E-cigs don’t have tar, so the main advantage to vaping is that you’re missing out on this cancer-causing cocktail.


There may be other harmful chemicals you’re getting, though. Diacetyl, used in some flavorings, is fine to eat but not to inhale. Mice exposed to e-cigarette vapor suffered mild lung damage, but far less than they would with cigarette smoke. And in a widely reported study, researchers found that e-cigarettes could produce more formaldehyde than tobacco cigarettes, but only if the heating element was cranked up to unusually high levels. While obviously vaping isn’t as safe as breathing clean air, it’s probably far better than smoking an actual cigarette.

Is that enough to declare e-cigarettes mostly harmless? The World Health Organization is pessimistic, but accurate, when they describe the unknowns:

The potential risks [e-cigarettes] pose for the health of users remain undetermined. Furthermore, scientific testing indicates that the products vary widely in the amount of nicotine and other chemicals they deliver and there is no way for consumers to find out what is actually delivered by the product they have purchased.


In other words, it’s the supplement problem all over again: nobody is verifying exactly what’s inside or how much of it there is, so you’re kind of on your own.


There’s one more source of danger that’s not in the vaporizer itself: the refill bottles contain concentrated nicotine that can be inhaled, swallowed, or absorbed through the skin. Drinking the liquid has led to at least one toddler’s death. Childproof caps aren’t currently mandated. If you use the liquid, handle it carefully and keep it out of reach of kids and pets.

Can Vaping Help You Quit Smoking?

Since e-cigarettes have fewer harmful components than tobacco cigarettes, it seems like a no-brainer that switching would be good for your health. But if that’s true, scientists are having a hard time proving it. The American Lung Association, for one, is “troubled by unproven claims” that e-cigarettes can help people quit; the science, they say, just isn’t there.




Take this study, published in JAMA Internal Medicine last year. Of tobacco smokers calling into a hotline for help quitting, the ones who used e-cigarettes were no more likely to quit in the end. The authors write that it’s possible vaping did help people quit, but at so low a rate that their study couldn’t detect it.



On the other hand, a study published in the journal Addiction found that smokers who used e-cigarettes to quit were 60% more likely to succeed than those who used nicotine patches. Why the opposite result? It’s not clear. These smokers were trying to quit on their own, not with a quit line, and there may be other important differences between the two studies.




The latest study adds another wrinkle: researchers report in the American Journal of Public Health that—not looking at quitters, but just at habitual smokers—those who used e-cigarettes were less likely to end up quitting smoking. In other words, vapers may not want to quit.



It’s possible that they figure they’ve reduced the amount of harm they’re doing to themselves, and thus a few cigarettes plus a vaping habit is better than an old-fashioned smoking habit. But without more research on their motivation, we can’t say for sure if this is what happening.




Success at quitting might also depend on factors like the nicotine dose you get from the e-cigarette, and how often you use it. There are no agreed-upon guidelines for using vaping as a smoking cessation aid. That means we don’t know whether it works to help people quit, and we can’t say how you should use it if that’s your goal.




Is Big Tobacco Behind the Rise In Vaping?

Traditional cigarette companies are in a weird position here: they’d love a piece of a market that keeps people interested in smoking, but they also want to protect their much larger market in actual tobacco.


The result is a sort-of war between two types of manufacturers. In one corner, we have independent companies selling refillable equipment at vape shops, often emphasizing the Baskin-Robbins-like array of available flavors. In the other, “cigalike” products you can buy at convenience stores: disposable, cigarette-looking, and cigarette-flavored. The biggest maker of these, Blu, is owned by a tobacco company (although the #2 brand, NJOY, is not).



Big Tobacco seems to be hedging their bets in a couple of ways: selling cigalikes slapped with warnings that make them look worse than cigarettes, while writing to the FDA that their “open system” competitors are dangerous and need more regulation.




Meanwhile, the independent e-cigarette companies are shaping up to be a marketing force of their own. As the market evolves, keep your eye on the science, not the hype.



Illustration by Tara Jacoby.

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