How e-liquid flavor affects smoking cessation.
Vaping is an emerging global phenomenon. Ten years ago, there were only about 7 million people using e-cigarettes in world; two years ago that number was 41 million , and it’s still growing. Young people are discovering them, adults are enthusiastically using them, long-term smokers are switching to them…and, increasingly, doctors are testing them as a way to help patients quit smoking.
The idea is pretty simple: traditional tobacco products like cigarettes, cigars, and pipes have well-known health risks. They’re full of tar and carbon monoxide, heavy metals and even radioactive compounds. Smoking them does physical harm to almost every part of our body, especially our lungs, and that causes all kinds of potentially fatal diseases.
E-cigarettes aren’t like that. They’re not risk free —we’ll get into this in a second—but they are much healthier than so-called “combustible” tobacco, meaning anything you smoke. The vapor that e-cigarettes produce can deliver the same sensation with lower health risks.
So, naturally, smoking experts and public health authorities have been examining them as a way to get people to quit smoking. E-cigarettes shouldn’t be assessed as a health benefit, exactly, but rather a reliable type of “harm reduction” when it comes to smoking. Quitting is hard, is often an ongoing struggle over the course of a lifetime, and any intermediate step is progress is the right direction—progress that can potentially save lives.
Any serious article on quitting is going to tell you that the evidence on e-cigarettes isn’t all in yet. They help some people, make it worse for others, and it varies a lot by product. So rather than trying to tackle the whole field, this article is going to focus on just one aspect of it: how e-liquid flavor affects smoking cessation. We’ll quickly cover health issues and vaping as a tool to quit smoking, then get into why flavor is such an important part of making that work.
E-Cigarettes and Health
Here’s the headline for this section: e-cigarettes have fewer negative health effects than combustible tobacco products, and the ones they do have are less intense. One survey of more than 19,000 e-cigarette users reported significantly fewer “adverse events” (like serious disease). In fact, the most common health issue participants mentioned was a sore throat, which faded over time. Another study—this one analyzing almost 3 million social media posts from e-cigarette users—checked whether people were mostly positive or mostly negative when they mentioned health effects. In other words, were the e-cigarettes helping or hurting? The answer was that for almost every category of symptom, users were upbeat.
On the other hand, e-cigarettes are not risk free. The New Zealand Ministry of Healths vaping information portal, Vaping Facts explains the best thing to inhale for your lungs health is fresh air.
Breathing anything into your lungs besides fresh air will have a risk associated with it which is why non-smokers should not vape. For this reason, while vaping is significantly less harmful than smoking, its unlikely to be harm free. Scientists will not be certain for many years of any long-term health risks associated with vaping.
In New Zealand, the Ministry of Health is taking an active role via the Vaping Regulatory Authority to continuously monitor the risks associated with vaping in addition to setting robust product safety standards and procedures.
The key harm reduction benefit of vaping comes from their lack of toxins. Above-board, high-quality nicotine e-cigarettes are comparatively toxin-free. In particular, harmful carbonyl emissions from combustible cigarettes are almost completely absent in newer vaporizer products, and levels of other dangerous compounds like diacetyl and acetyl propionyl are about 1/10th what they are in combustible tobacco. In people who abandon smoking for e-cigarettes, levels of heavy metals, carbon monoxide, acrolein, and other negative biomarkers can drop by as much as 80%.
Overall, the advantages of vapor over smoke are considerable. Here’s a recent review by two prominent researchers:
“While e-cigarettes may have adverse effects on respiratory health and possibly other diseases, the harm is generally accepted to be much less than that of cigarette smoking. Thus, if smokers were to switch completely to e-cigarettes, then smoking-related disease is predicted to decrease substantially. Population-based models of the impact of e-cigarette use predict an overall health benefit.”
The World Health Organization (WHO) agreed in 2019, writing, “the available evidence indicates a possible positive effect of [e-cigarettes] on population health, particularly if appropriate regulation is enacted to maximize their benefits and minimize their risks.” In other words, if we care about public health, we should want every smoker to switch to e-cigarettes. The question is, will they?
As the American Centers for Disease Control and Prevention point out , just adding e-cigarettes to an existing smoking habit does nothing you your help. You need to quit using combustible tobacco entirely.
That means the new e-cigarette habit has to stick, and for that, it’s got to be at least as enjoyable as smoking—if not more so. That’s probably why e-liquid flavor turns out to be an important piece of quitting smoking, and why the existing evidence on quitting is a little mixed. Here’s the World Health Organization again:
“[E-cigarette use] could be effective in cessation for some smokers under some circumstances, while, for other smokers, in different circumstances, it might have the opposite effect. Whether an [it] has beneficial or detrimental effects on smoking cessation appears to depend on the technology, the motivation and consumer behaviour of the user, the type of smoker who seeks [e-cigarette] use, and the regulatory environment.”
In other words, it depends. The fact that e-cigarettes sometimes hurt and sometimes help explains results like the finding that overall, people using e-cigarettes are 28% less likely to quit smoking in the next 6 months. But the same study reported that if you narrow the field to only people who are actually trying to quit, it becomes roughly a wash, and if you look only at high-quality trials of e-cigarettes a a supervised quitting aid, they’re a net positive.
Two other big studies back that up. One was in the UK, looking at 900 people in a medical smoking cessation program. Half got standard nicotine replacement products, and the other half got e-cigarettes. A year later, only 9.9% of the first group was still smoke-free. For e-cigarette users, the number was 18%. Almost double. (There’s one caveat, though: at the one-year mark, only one in ten people were still using nicotine patches, while eight in ten were still using e-cigarettes.)
The other big piece of evidence we have comes from the prestigious Cochrane health policy institute. Their most recent review found that six months after switching from smoking to vaping, 9% of people using nicotine e-cigarettes were still abstinent. (That number drops to 4% for nicotine-free products.)
So we know that e-cigarettes can be useful for quitting. If people like e-cigarettes at least as much as they like traditional tobacco products, then the price advantage and health benefits should be enough to make the change stick.
That brings us to flavor. In the report we just heard from, the WHO looked at variation in products by comparing amount of nicotine released, nicotine level in the e-liquid, labeling, and quality control. What they don’t pay attention to is flavor, which turns out to be pretty important.
The Critical Role of Flavours
We know that flavored e-cigarettes help people quit thanks to four big pieces of evidence.
First, there’s the direct evidence. Using flavored e-cigarettes instead of “unflavored” (that is, tobacco-flavored) ones is correlated with an increase in quitting among adults who are 25 or older, according to analyses of huge datasets from the UK. We don’t know for sure whether this explains some of the variation in the studies we just talked about in the last section, but that’s certainly a possibility. In another investigation with almost 900 “dual users” of e-cigarettes and traditional cigarettes, just over 11% of them had quit smoking two years later. If you break that down by flavor, though, only 9.6% of people using unflavored vapes had quit, while the quit rate was 13.8% for people using sweet flavors.
The second piece of evidence is mentioned in that same study: over time, habitual e-cigarette users tend to shift away from unflavored or tobacco-flavored products, and toward sweeter, fruitier products. These are the long-term users—the one’s who’ve committed to switching away from cigarettes, just the way public health officials are hoping they will. And when you zero in on flavor preference, that pattern gets even more pronounced. In a group of almost 400 people, usage of tobacco-flavored e-liquids dropped from 40% to just 22%, while fruity flavors stayed constant (23%) and sweet ones jumped from 16% to 29%. For people who only sued e-cigarettes—never combustible tobacco—preference for fruity flavors was much higher, at 31%. A huge online survey found the same pattern, with long-term users moving away from unflavored products and toward sweeter, more heavily flavored ones. Flavor, in other words, seems to be related to stable, exclusive, long-term use.
The same survey gives us our third piece of evidence, a hint about why that relationship might be there. It flat-out asked participants how much flavor mattered to them in their efforts to quit smoking, and most said that it was “very important,” giving it a 4 out of 5 on a scale of helpfulness. Almost 50% of them said they would crave cigarettes more without access to flavored e-liquids, and 40% said not having flavored products would make it harder for them to quit.
Those opinions—that flavored e-liquids make it easier to quit—are backed up by the data. A group of researchers took 90 current smokers who weren’t intending to quit, and asked them to swap their cigarettes for e-cigarettes for six weeks. Overall, people’s average smoking rate dropped from 16 to 7 cigarettes per day. But flavor made a big difference: participants given menthol e-cigarettes had the largest drop in smoking, while those with tobacco and cherry e-cigarettes daw the largest increase in vaping. That fits our pattern: use of e-cigarettes is linked to flavor, with tobacco being most popular at first and sweet, fruity flavors driving longer-term use.
Two other studies looking at current or former “dual users” back that up. Smokers who either have quit or tried to quit are much more likely to have used fruity or sweet e-cigarettes. Smokers who just add e-cigarettes to regular ones tend to stick with unflavored products. So that’s our fourth piece of evidence: choosing flavored e-cigarettes seems to help you quit.
Finally, there’s the fifth piece of evidence. For most people, most of the time, flavored products just make vaping better. In flavor tests, “harshness” and “bitterness” are rated as the worst parts of using an e-cigarette. Those are the things people like least. And adding in minty, sugary, or fruity flavoring helps to cover up those harsh, bitter elements, which are caused by nicotine. If you ask people why they used flavored products, the two most popular responses are “increased enjoyment” and “they taste better than cigarettes.” And if you put people in a lab and give them an e-cigarette, they’ll tell you they like a sweet-flavored version more, then they’ll work four times as hard to get access to it in a point-and-click task, and then, if allowed to vape freely, they’ll use the flavored product at twice the rate of an unflavored one.
Here’s how that all stacks up:
- Use of flavored e-cigarettes is correlated with higher rates of quitting.
- Use of flavored e-cigarettes is also correlated with longer use, and with more exclusive use (meaning, less simultaneous use of regular cigarettes).
- Users say that the flavors make it easier to quit, and make them crave cigarettes less intensely and less often.
- Flavored e-cigarette use is more common among current and former smokers who quit or have tried to quit, and is correlated with smoking fewer cigarettes per day in “dual users.”
- Finally, people just like flavored e-cigarettes better. They work harder for them, enjoy them more, and say that they deliver a more pleasant experience overall—when compared to unflavored e-cigarettes or regular combustible tobacco.
Of course, that’s not the end of the story. The science is is complicated, and is evolving rapidly. Dozens of major studies are underway right now, any one of which might shift our understanding of the relationships between e-cigarettes, smoking cessation, flavor, and enjoyment.
But for right now, the evidence looks pretty clear: Vape flavours matter! Vaping flavored eliquids helps us quit, helps us stay smoke free, and, as an added bonus, it makes e-cigarettes more enjoyable to a traditional cigarette.
Audrain-McGovern, J., Strasser, A. A., & Wileyto, E. P. (2016). The impact of flavoring on the rewarding and reinforcing value of e-cigarettes with nicotine among young adult smokers. Drug and Alcohol Dependence, 166, 263-267.
Baker, T. B., & Fiore, M. C. (2020). What We Do Not Know About e-Cigarettes Is a Lot. JAMA Network Open, 3(6), e204850-e204850.
Berg, C. J. (2016). Preferred flavors and reasons for e-cigarette use and discontinued use among never, current, and former smokers. International Journal of Public Health, 61(2), 225-236.
Chen, L., Lu, X., Yuan, J., Luo, J., Luo, J., Xie, Z., & Li, D. (2020). A social media study on the associations of flavored electronic cigarettes with health symptoms: Observational study. Journal of Medical Internet Research, 22(6), e17496.
Du, P., Bascom, R., Fan, T., Sinharoy, A., Yingst, J., Mondal, P., & Foulds, J. (2020). Changes in flavor preference in a cohort of long-term electronic cigarette users. Annals of the American Thoracic Society, 17(5), 573-581.
Farsalinos, K. E., Romagna, G., Tsiapras, D., Kyrzopoulos, S., Spyrou, A., & Voudris, V. (2013). Impact of flavour variability on electronic cigarette use experience: an internet survey. International Journal of Environmental Research and Public Health, 10(12), 7272-7282.
Farsalinos, K. E., Romagna, G., Tsiapras, D., Kyrzopoulos, S., & Voudris, V. (2014). Characteristics, perceived side effects and benefits of electronic cigarette use: a worldwide survey of more than 19,000 consumers. International Journal of Environmental Research and Public Health, 11(4), 4356-4373.
Farsalinos, K. E., Kistler, K. A., Gillman, G., & Voudris, V. (2015). Evaluation of electronic cigarette liquids and aerosol for the presence of selected inhalation toxins. Nicotine & Tobacco Research, 17(2), 168-174.
Farsalinos, K. E., & Gillman, G. (2018). Carbonyl emissions in e-cigarette aerosol: a systematic review and methodological considerations. Frontiers in Physiology, 8, 1119.
Friedman, A. S. (2020). Association of vaping‐related lung injuries with rates of e‐cigarette and cannabis use across US states. Addiction.
Friedman, A. S., & Xu, S. (2020). Associations of flavored e-cigarette uptake with subsequent smoking initiation and cessation. JAMA Network Open, 3(6), e203826-e203826.
Hajek, P., Phillips-Waller, A., Przulj, D., Pesola, F., Myers Smith, K., Bisal, N., ... & McRobbie, H. J. (2019). A randomized trial of e-cigarettes versus nicotine-replacement therapy. New England Journal of Medicine, 380(7), 629-637.
Hartmann-Boyce, J., McRobbie, H., Lindson, N., Bullen, C., Begh, R., Theodoulou, A., ... & Hajek, P. (2020). Electronic cigarettes for smoking cessation. Cochrane Database of Systematic Reviews, 10.
O’Leary, R., Polosa, R., & Volti, G. L. (2021). Critical appraisal of the European Union Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) Preliminary Opinion on electronic cigarettes. Harm Reduction Journal, 18(1), 1-15.
Kalkhoran, S., & Glantz, S. A. (2016). E-cigarettes and smoking cessation in real-world and clinical settings: a systematic review and meta-analysis. The Lancet Respiratory Medicine, 4(2), 116-128.
Kasza, K. A., Goniewicz, M. L., Edwards, K. C., Sawdey, M. D., Silveira, M. L., Gravely, S., ... & Hyland, A. (2021). E-Cigarette Flavors and Frequency of E-Cigarette Use among Adult Dual Users Who Attempt to Quit Cigarette Smoking in the United States: Longitudinal Findings from the PATH Study 2015/16–2016/17. International Journal of Environmental Research and Public Health, 18(8), 4373.
Kim, H., Lim, J., Buehler, S. S., Brinkman, M. C., Johnson, N. M., Wilson, L., ... & Clark, P. I. (2016). Role of sweet and other flavours in liking and disliking of electronic cigarettes. Tobacco Control, 25(Suppl 2), ii55-ii61.
Kim, S. A., Smith, S., Beauchamp, C., Song, Y., Chiang, M., Giuseppetti, A., ... & Kim, J. J. (2018). Cariogenic potential of sweet flavors in electronic-cigarette liquids. PLoS ONE, 13(9), e0203717.
Li, L., Borland, R., Cummings, K. M., Fong, G. T., Gravely, S., Smith, D. M., ... & McNeill, A. (2021). How does the use of flavored nicotine vaping products relate to progression towards quitting smoking? Findings from the 2016 and 2018 ITC 4CV Surveys. Nicotine & Tobacco Research.
Litt, M. D., Duffy, V., & Oncken, C. (2016). Cigarette smoking and electronic cigarette vaping patterns as a function of e-cigarette flavourings. Tobacco Control, 25(Suppl 2), ii67-ii72.
Prochaska, J. J., & Benowitz, N. L. (2019). Current advances in research in treatment and recovery: Nicotine addiction. Science Advances, 5(10), eaay9763.
Pullicin, A. J., Kim, H., Brinkman, M. C., Buehler, S. S., Clark, P. I., & Lim, J. (2020). Impacts of nicotine and flavoring on the sensory perception of e-cigarette aerosol. Nicotine and Tobacco Research, 22(5), 806-813.
Rosbrook, K., & Green, B. G. (2016). Sensory effects of menthol and nicotine in an e-cigarette. Nicotine & Tobacco Research, 18(7), 1588-1595.
Soule, E. K., Lopez, A. A., Guy, M. C., & Cobb, C. O. (2016). Reasons for using flavored liquids among electronic cigarette users: A Concept Mapping Study. Drug and Alcohol Dependence, 166, 168-176.
Wang, R. J., Bhadriraju, S., & Glantz, S. A. (2020). E-Cigarette Use and Adult Cigarette Smoking Cessation: A Meta-Analysis. American Journal of Public Health, (0), e1-e17.
World Health Organization. (2019). WHO Study Group on Tobacco Product Regulation. Report on the scientific basis of tobacco product regulation: Seventh report of a WHO study group. Geneva: World Health Organization. https://apps.who.int/iris/bitstream/handle/10665/329445/9789241210249-eng.pdf
Zare, S., Nemati, M., & Zheng, Y. (2018). A systematic review of consumer preference for e-cigarette attributes: flavor, nicotine strength, and type. PloS ONE, 13(3), e0194145.