A decade ago, most smokers believed vaping was less harmful than cigarettes. Today, the opposite is true: a majority now say vapes are as dangerous or worse. That shift is visible in survey data and reflects a large change in public conversation about e-cigarettes.
Why has opinion turned negative? Partly because the headlines have been alarming. Partly because vaping has become far more common and visible — the smell of tobacco in public places has been largely replaced by fruity vape scents. In the UK nearly as many people vape as smoke, about one in ten adults, and vaping has risen fast while smoking fell dramatically over the last few decades.
Is that a good thing? Or are people swapping one harmful habit for another? Below I answer the most common questions about vaping: how its health risks compare to smoking, whether it helps people quit, whether it’s a gateway to smoking for young people, and other frequent concerns.
How do the health risks of vaping compare to cigarettes?
This is the central question. If vaping were just as bad as smoking, replacing cigarettes with e-cigarettes would not improve health. The best available evidence, however, indicates vaping is substantially less harmful than smoking — though not risk-free.
When you burn a cigarette, combustion produces thousands of chemicals, many toxic or carcinogenic: tar, carbon monoxide, benzene, cadmium, polycyclic aromatic hydrocarbons, and more. Smoking raises the risk of lung cancer, stroke, heart disease and a range of other illnesses. In the UK, smoking is the leading risk factor for early death.
E-cigarettes work differently. They heat a liquid to produce an aerosol rather than burning tobacco, so far fewer harmful toxins are generated. Many vapes do contain nicotine, which is addictive and can affect heart rate and blood pressure, and is not recommended in pregnancy. Vapes also include solvents, flavorings and small amounts of metals from coils — these can irritate the lungs or worsen conditions like asthma — but overall the exposure to the most dangerous chemicals found in cigarette smoke is much lower.
We don’t have decades of long-term epidemiological data on vaping the way we do for smoking, but e-cigarettes have been widely used for around 20 years. If vaping produced harms anywhere near those of smoking, we would expect to see clearer warning signs by now. Given what we know about ingredients and exposure, major public health bodies generally conclude vaping is much less harmful than smoking. They advise against vaping for young people and non-smokers, but recommend e-cigarettes as a quitting aid for smokers.
A concise summary: “If you smoke, vaping is much safer; if you don’t smoke, don’t vape.” — Chris Whitty, Chief Medical Officer for England
Do vapes deliver more nicotine than cigarettes?
There’s a common claim that a single vape equals the nicotine of dozens of cigarettes. The honest answer is: nicotine uptake varies a lot by product and by user, but typical nicotine exposure for a vaper and for a smoker can be similar.
A packet of 20 cigarettes contains about 200–300 mg of nicotine (10–15 mg per cigarette), but only a small fraction is absorbed — roughly 1–1.5 mg per cigarette, or 20–30 mg per pack. In the UK the legal limit for e-liquids is 20 mg nicotine per milliliter; a 2 ml device therefore contains 40 mg, and roughly half of that may be absorbed — around 20 mg. That’s comparable to the nicotine absorbed from a pack of cigarettes. How long a vape lasts depends on how heavily someone vapes: a moderate user might get one to two days of use from a disposable, similar to a pack of cigarettes; light users might stretch it to a week; heavy users can finish one in a day.
Overall, average daily nicotine intake is similar between many e-cigarette users and smokers, although peak blood nicotine levels from vaping tend to be lower than from a cigarette.
Are e-cigarettes harmful during pregnancy?
Headlines sometimes claim vaping in pregnancy is as dangerous as smoking. Much of this reporting rests on limited animal studies or low-quality human studies. For example, a small mouse study exposed a handful of pregnant mice to nicotine vapor and found developmental differences in offspring — but extrapolating from that tiny animal experiment to humans is tenuous.
Human studies on vaping in pregnancy are mostly low quality and give mixed results. Some comparisons show no clear difference in birth outcomes between vapers and non-users; others show no clear difference between vapers and smokers — an inconsistent picture that reflects poor study design. Nicotine can cross the placenta and may affect fetal development, so it’s plausible vaping raises some risks compared to using no nicotine at all. But because e-cigarettes lack many of the harmful combustion products in cigarettes, we should expect vaping to be less risky than smoking during pregnancy.
If pregnant people can quit nicotine entirely, that’s best. If quitting completely proves impossible, switching from smoking to vaping is likely to be less harmful than continuing to smoke.
Does vaping cause “popcorn lung”?
“Popcorn lung” — bronchiolitis obliterans — became a public concern because diacetyl, a flavoring once used in microwave popcorn factories, was linked to lung damage in workers. Diacetyl was also used in some e-liquid flavorings, prompting fears e-cigarettes would cause the same disease. But there have been no reported cases of popcorn lung among vapers, and cigarette smokers are exposed to much higher diacetyl levels than vapers yet haven’t shown cases attributable to it. Diacetyl has been banned in many countries for e-liquids. Overall, the evidence linking vaping to popcorn lung is weak.
Are e-cigarettes an effective quitting tool?
Many smokers want to quit but struggle to do so. The research suggests e-cigarettes are the most effective tool currently available.
Independent reviews, including recent Cochrane evidence, found high-certainty evidence that people using e-cigarettes are more likely to stop smoking than those using other nicotine replacement therapies (patches, gum). There is moderate evidence that nicotine-containing e-cigarettes are more effective than non-nicotine versions.
In Britain, quit rates have risen over the past decade alongside the rapid rise of vaping. More than half of British smokers who quit in the last five years reported using e-cigarettes in their final successful attempt — roughly 2.4 million people. Many ex-smokers still use vapes; some have also quit vaping. E-cigarettes are not the only factor in higher quit rates, but they have likely contributed.
One caveat: if someone both vapes and keeps smoking the same number of cigarettes, their health doesn’t improve. The benefit comes when vaping replaces cigarettes or significantly reduces smoking.
What do current smokers think about vaping?
Perceptions matter. Surveys show ex-smokers and current smokers who vape are more likely to say vaping is less harmful than smoking. But current smokers who do not vape — either never tried or tried and stopped — tend to believe e-cigarettes are as harmful or more harmful than cigarettes. That perception gap is important because many smokers who might benefit from switching to vaping avoid it due to safety worries or reluctance to substitute one addiction for another. Around a third cite safety concerns or fear of swapping addictions; another 13% doubt vaping would help them quit. In short, many smokers avoid trying e-cigarettes for reasons that contradict much of the scientific evidence.
How common is vaping among people who have never smoked?
In Great Britain about 10% of adults vape — roughly 4.7 million people. Most vapers are current or former smokers. There are about 300,000 vapers who have never smoked, roughly 1% of never-smokers. That’s a small share today, but as overall smoking declines and younger generations age, the proportion of vapers who never smoked could grow.
How common is vaping among young people, and is it a gateway to smoking?
Concerns about youth vaping are legitimate. Most people who become addicted to smoking start as teenagers, and younger age groups vape more than older ones: nearly 30% of 16–24-year-olds report vaping at least occasionally, compared to much lower shares in older groups.
Is vaping a gateway to cigarettes? At the individual level, young people who vape are more likely to later try smoking than young people who don’t vape. But that association does not prove causation: young people prone to risk-taking or addiction may be more likely both to vape and later to smoke. Some reviews find very low-certainty evidence that, at the population level, increased vaping has coincided with declines in youth smoking.
Population data give useful context. Despite rising youth vaping, smoking rates among teenagers in England and the US have continued to fall sharply in recent decades. In England, only a few percent of 15-year-olds now smoke regularly, a dramatic decrease from past decades. These trends suggest that, so far, youth vaping has not led to large increases in youth cigarette smoking, though the modest risk that vaping increases nicotine exposure among teens who would never have smoked remains a public-health concern.
Balancing benefits and risks
E-cigarettes can meaningfully help adult smokers quit and are substantially less harmful than smoking. Yet vaping is not risk-free, nicotine is addictive, and youth uptake is worrying. Policymakers face the difficult task of promoting e-cigarettes as an effective cessation tool for adults who smoke while limiting access and appeal to young people and never-smokers.
Smoking remains uniquely harmful: it’s the leading risk factor for early death in many countries and causes more than six million deaths a year globally. The mistaken belief that vaping is as bad as smoking means many smokers miss an effective way to quit. Closing that perception gap could save lives.
Acknowledgments
Thanks to Max Roser, Edouard Mathieu, Simon van Teutem, Fiona Spooner for feedback, and Marwa Boukarim for work on visualizations.
This article was adapted from an original report published on ourworldindata.org. All rights belong to the original publisher.