ENDS Adults Who Smoke

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Studies, Surveys, Papers, and Case Studies

  • Sometimes it's necessary to view the PDF version to access the full study.
  • This page is for referencing the possible benefits of ENDS products vs. smoking cigarettes by adults. (Electronic Nicotine Delivery Systems are also known as vapor technology, ecigarettes, ecigs, EVP - electronic vapor product, etc.). They may also be referred to as ANDS - Alternative Nicotine Delivery System and SNP - safer nicotine product.



Dual Use

2021: Regulation of e-cigarette flavours – a response

  • Testimony in Netherlands pertaining to a potential flavour / flavor ban. This document responds to the proposed Decree of the State Secretary for Health, Welfare and Sport on the regulation of e-cigarette flavours in the Netherlands.
  • Signed by 24 experts from around the world
  • Covers 12 key points
    • Sets conflicting objectives and takes a “war on drugs” approach to nicotine.
    • Adopts false and misleading claims about the risks of e-cigarettes.
    • Draws on irrelevant information about an outbreak of lung injuries in North America.
    • Misunderstands “dual-use”.
    • Asserts a “gateway effect” but there is more likely to be a diversion away from smoking.
    • Takes a simplistic approach to youth risk behaviours and fails to demonstrate benefits to adolescent public health.
    • Ignores perverse consequences of prohibition, even though these are foreseeable.
    • Fails to show benefits for adolescents or address concerns it may cause harm to young people.
    • Ignores the harmful effects of a vaping flavour ban on adults.
    • Creates regulatory protection for the cigarette trade.
    • Violates important regulatory principles, including those underpinning the European Union internal market.
    • Proposes an illiberal policy and fails to recognise a major global public health opportunity.
  • Acknowledgement: We confirm that signatories report no conflicts with respect to FCTC Article 5.3 and no financial conflicts of interest with respect to tobacco or e-cigarette companies under the International Committee of Medical Journal Editors (ICJME) reporting standard.


2019: 2019 Perceived relative harm of using e-cigarettes predicts future product switching among US adult cigarette and e-cigarette dual users

  • Compared with those with other perceptions of e‐cigarette harm, dual users who perceived e‐cigarettes as less harmful than cigarettes were more likely to become exclusive e‐cigarette users 1 year later.
  • PDF Version


2019: Vaping patterns, nicotine dependence and reasons for vaping among American Indian dual users of cigarettes and electronic cigarettes

  • The ten-item Penn State Dependence Index (PSDI) suggested greater dependence on smoking than vaping
  • The most common reasons for vaping were to reduce smoking (79%), enjoyment of flavors (78%), and ability to vape where smoking is not allowed (73%). Perceptions of less harm to others (69%) or to self were the next most common (65%). Fewer than half used ECs to reduce stress, for affordability, or because others used them.
  • PDF Version
  • Citation: Rhoades DA, Comiford AL, Dvorak JD, Ding K, Hopkins M, Spicer P, Wagener TL, Doescher MP. Vaping patterns, nicotine dependence and reasons for vaping among American Indian dual users of cigarettes and electronic cigarettes. BMC Public Health. 2019 Sep 2;19(1):1211. doi: 10.1186/s12889-019-7523-5. PMID: 31477072; PMCID: PMC6721166.
  • Acknowledgement: Grants from the National Cancer Institute of the National Institutes of Health (P20CA202921 to University of Oklahoma, and 5P20CA202923 to Cherokee Nation) supported this study.


2019: Young adult dual combusted cigarette and e-cigarette users’ anticipated responses to hypothetical e-cigarette market restrictions

  • Hypothetical regulations resulted in reported intentions to reduce EC (e-cigarette) use and increase CC (combustible cigarette) use; the greatest impact was found for restrictions regarding e-liquid nicotine content, followed by flavor
  • This work provides preliminary evidence that restrictive regulations regarding key EC characteristics may increase intentions to increase CC use among young adult dual EC and CC users.
  • PDF Version
  • Citation:: Lauren R. Pacek, Olga Rass, Maggie M. Sweitzer, Jason A. Oliver & F. Joseph McClernon (2019): Young adult dual combusted cigarette and e-cigarette users’ anticipated responses to hypothetical e-cigarette market restrictions, Substance Use & Misuse, DOI:10.1080/10826084.2019.1626435
  • Acklnowledgement: This work was supported by the National Institutes of Health (K01DA043413, K23DA039294, and K23DA042898). The funding source had no other role other than financial support.


2017: Differences between Dual Users and Switchers Center around Vaping Behavior and Its Experiences Rather than Beliefs and Attitudes

  • To the extent that dual users substantially lower the number of cigarettes, they will reduce health risks from smoking. However, from a medical point of view, exclusive vaping is preferable to dual use;
  • Differences between dual users and switchers center around variables proximal to the vaping behavior and its experienced effects rather than hinging on more general vaping-related beliefs and attitudes.
  • After e-cig initiation, dual users decreased tobacco consumption by 82% and were low-to-moderately cigarette dependent.
  • The two groups (dual users and switchers) reported mostly using a flavor other than tobacco.
  • PDF Version
  • Citation: Adriaens K, Van Gucht D, Baeyens F. Differences between Dual Users and Switchers Center around Vaping Behavior and Its Experiences Rather than Beliefs and Attitudes. Int J Environ Res Public Health. 2017 Dec 23;15(1):12. doi: 10.3390/ijerph15010012. PMID: 29295483; PMCID: PMC5800112.

Economic Impact

2019: The Impact of Electronic Cigarettes on Cigarette Smoking By Americans and Its Health and Economic Implications

  • In this study, we examined the growing use of electronic cigarettes and its implications. The wide use of e-cigarettes is a very recent development, and issues regarding their long-term effects and significance cannot be fully analyzed at this time. Using CDC and other data covering the last decade, however, we examined the relationship between the recent sharp increase in e-cigarette use among Americans and the contemporaneous acceleration in the declining rate of cigarette smoking.
  • We found that the sharp increase in e-cigarette use across many groups can explain as much as 70 percent of the accelerating decline in smoking rates. We also found no reasonable evidential basis for concerns that e-cigarettes are a gateway to cigarette smoking.
  • We further found that e-cigarettes are highly effective in helping people stop smoking cigarettes.
  • Finally, we analyzed the impact of the sharp increase in e-cigarette use and the accelerating decline in cigarette smoking on healthcare costs and economic productivity. *We found that while e-cigarette users incur lower healthcare costs than cigarette smokers or ex-smokers, the longer lifespans of e-cigarette users and ex-smokers who used e-cigarettes to quit smoking result in higher lifetime healthcare costs. However, we also found that the value of the additional years of life associated with using e-cigarettes instead of smoking is much greater than the additional healthcare costs.
  • Lastly, we found that the increase in e-cigarette use and the associated reduction in smoking rates results in large productivity benefits, mainly from lower rates of illness.
  • PDF Version


2019: Cost‐effectiveness of e‐cigarettes compared with nicotine replacement therapy in stop smoking services in England (TEC study): a randomized controlled trial

  • Using e‐cigarettes as a smoking cessation aid with standard behavioural (behavioral) support in stop‐smoking services in England is likely to be more cost‐effective than using nicotine replacement therapy in the same setting.
  • PDF Version


2019: Expenditure on smoking and alternative nicotine delivery products: a population survey in England

  • In England, expenditure among e‐cigarette and nicotine replacement therapy users is approximately one‐third of the expenditure of smokers. The average smoker may save an estimated £15.06 per week by switching completely to e‐cigarettes or £13.04 per week by switching to nicotine replacement therapy, although this is likely to differ according to individual usage patterns.
  • PDF Version


2018: Behavioral Economic Purchase Tasks to Estimate Demand for Novel Nicotine/tobacco Products and Prospectively Predict Future Use: Evidence From The Netherlands

  • Smokers valued FMCs [factory made cigarettes] more than ECs [electronic cigarettes] or VLNCs, [very low nicotine cigarettes] and FMCs were less sensitive to price increases. Demand indices predicted use of commercially available products over a 15 month period.
  • To serve as viable substitutes for FMCs, ECs and VLNCs will need to be priced lower than FMCs.
  • PDF Version


Flavors

2021: Regulation of e-cigarette flavours – a response

  • Testimony in Netherlands pertaining to a potential flavour / flavor ban. This document responds to the proposed Decree of the State Secretary for Health, Welfare and Sport on the regulation of e-cigarette flavours in the Netherlands.
  • Signed by 24 experts from around the world
  • Covers 12 key points
    • Sets conflicting objectives and takes a “war on drugs” approach to nicotine.
    • Adopts false and misleading claims about the risks of e-cigarettes.
    • Draws on irrelevant information about an outbreak of lung injuries in North America.
    • Misunderstands “dual-use”.
    • Asserts a “gateway effect” but there is more likely to be a diversion away from smoking.
    • Takes a simplistic approach to youth risk behaviours and fails to demonstrate benefits to adolescent public health.
    • Ignores perverse consequences of prohibition, even though these are foreseeable.
    • Fails to show benefits for adolescents or address concerns it may cause harm to young people.
    • Ignores the harmful effects of a vaping flavour (flavor) ban on adults.
    • Creates regulatory protection for the cigarette trade.
    • Violates important regulatory principles, including those underpinning the European Union internal market.
    • Proposes an illiberal policy and fails to recognise a major global public health opportunity.
  • Acknowledgement: We confirm that signatories report no conflicts with respect to FCTC Article 5.3 and no financial conflicts of interest with respect to tobacco or e-cigarette companies under the International Committee of Medical Journal Editors (ICJME) reporting standard.


2020: Paper: Intended and Unintended Effects of Banning Menthol Cigarettes

  • Menthol bans significantly increased non-menthol cigarette smoking among youths, resulting in no overall net change in youth smoking rates.
  • Menthol bans shifted smokers’ cigarette purchases away from grocery stores and gas stations to First Nations reserves (where the menthol bans do not bind).
  • PDF Full Paper


2020: Associations of Flavored e-Cigarette Uptake With Subsequent Smoking Initiation and Cessation

  • Adults who began vaping nontobacco-flavored e-cigarettes were more likely to quit smoking than those who vaped tobacco flavors.
  • Banning flavors altogether may be too blunt an instrument for the current problem (youth use of vapor products).
  • PDF Version
  • Citation: Friedman, A. S., & Xu, S. (2020). Associations of Flavored e-Cigarette Uptake With Subsequent Smoking Initiation and Cessation. JAMA Network Open, 3(6), e203826. doi:10.1001/jamanetworkopen.2020.3826
  • Acknowledgment: : Ms Xu was supported by a T32 National Research Service Award from the Agency for Healthcare Research and Quality (HS017589).


2020: Association of vaping‐related lung injuries with rates of e‐cigarette and cannabis use across US states

  • Policymakers should proceed with caution when considering bans on flavored nicotine e‐liquids: restricting legal sales may push some vapers towards illicit sources, user‐modified e‐liquids (e.g. to add flavoring) or even conventional cigarette use. Given EVALI’s potential lethality and a myriad of work suggesting that conventional cigarette use is probably far more dangerous than vaping nicotine, these outcomes could be disastrous for public health. There is no link between nicotine liquids and EVALI. It appears to have come from illicit cannabis products.
  • Link above is to the PDF version
  • Citation: Friedman, A. S. (2020). Association of Vaping‐related Lung Injuries with Rates of E‐cigarette and Cannabis Use across US States. Addiction. doi:10.1111/add.15235
  • Acknowledgement: Research reported in this publication was supported by grant number 3U54DA036151‐08S2 from the National Institute On Drug Abuse of the National Institutes of Health and FDA Center for Tobacco Products (CTP).


2020: Reported patterns of vaping to support long-term abstinence from smoking: a cross-sectional survey of a convenience sample of vapers

  • Qualitative research suggests e-cigarettes can meet many of the needs of ex-smokers by substituting physical, psychological, social, cultural and identity-related aspects of tobacco addiction.
  • According to a time-series analysis of data from the Smoking Toolkit study, in which repeated cross-sectional surveys are conducted with a representative sample of households in England, increasing prevalence of e-cigarette use in current smokers was predictive of higher success rates of quit attempts.
  • Most participants were self-reported long-term abstinent smokers (86.3%).
  • Those who start on a low self-reported nicotine e-liquid concentration (strength) will be more likely to relapse to tobacco smoking than those starting on a higher nicotine e-liquid, after controlling for cigarettes per day (CPD) before cessation.
  • Results suggest a change in flavor choices over the course of vaping initiation and uptake. There was a reduction in the proportion of people using a tobacco flavor, and increase in the proportion using a fruit/sweet/food flavor, from initial to current flavor choice
  • According to the 2017 ASH-A survey, among current users, fruit flavors were the most popular.
  • PDF Version
  • Citation: Gentry, S.V., Ward, E., Dawkins, L. et al. Reported patterns of vaping to support long-term abstinence from smoking: a cross-sectional survey of a convenience sample of vapers. Harm Reduct J 17, 70 (2020). doi:10.1186/s12954-020-00418-8
  • Acknowledgement: This research was funded by Cancer Research UK (CRUK), Grant Number C54889/A22732.


2020: The impact of a comprehensive tobacco product flavor ban in San Francisco among young adults

  • Among the 18–24 age group, there was a significant increase in cigarette smoking.
  • Cigarette smoking increased among 25–34 years old.
  • Banning flavors in e-cigarettes can push some e-cigarette users to turn to cigarette smoking and could prompt some youth to initiate into smoking instead of e-cigarette use.
  • The proportions of e-cigarettes, cigarettes, and cigars obtained over the internet increased after the ban, and the proportions obtained from retailers outside of San Francisco also increased overall.
  • PDF Version
  • Citation: Yang, Y., Lindblom, E. N., Salloum, R. G., & Ward, K. D. (2020). The impact of a comprehensive tobacco product flavor ban in San Francisco among young adults. Addictive Behaviors Reports, 11, 100273. doi:10.1016/j.abrep.2020.100273
  • Acknowledgement: This research was supported by the National Institute of Drug Abuse of the National Institutes of Health (R03DA048460).


2019: Changes in Flavor Preference in a Cohort of Long-Term Electronic Cigarette Users

  • Our results regarding anticipated reactions to FDA e-cigarette flavor regulation suggest complexities such that the benefits and risks of flavor ban need to be carefully evaluated.
  • A majority anticipated that they would personally attempt to circumvent potential FDA regulations of e-cigarettes by obtaining e-cigarette flavors from various illicit sources (e.g., Internet orders from foreign countries) or even self-making flavors.
  • The use of flavoring agents purchased from unregulated sources could lead to additional unanticipated toxicities.
  • It is also concerning that some established e-cigarette users believed that they would return to cigarette smoking if nontobacco e-cigarette flavors were banned. Thus, for adult e-cigarette users who use certain flavors to facilitate smoking cessation or reduction, banning all nontobacco flavors could precipitate relapse to smoking.
  • PDF Version
  • Citation: Ann Am Thorac Soc Vol 17, No 5, pp 573–581, May 2020, Copyright © 2020 by the American Thoracic Society, DOI: 10.1513/AnnalsATS.201906-472OC
  • Acknowledgement: Supported by the National Institute on Drug Abuse of the National Institutes of Health (NIH) and the Center for Tobacco Products of the U.S. Food and Drug Administration (FDA) (P50-DA-036107) for the Penn State Tobacco Center of Regulatory Science.


2019: The role of flavors in vaping initiation and satisfaction among U.S. adults

  • Most common reasons for vaping initiation were as an alternative to cigarettes (43.7%) and because respondents viewed e-cigarettes as less harmful than other tobacco products (31.2%). Flavor was the third most commonly reported reason.
  • Satisfaction among those who bought flavored e-liquid was higher than those who did not buy flavored e-liquid.
  • PDF Version
  • Citation: Landry, R. L., Groom, A. L., Vu, T.-H. T., Stokes, A. C., Berry, K. M., Kesh, A., … Payne, T. J. (2019). The role of flavors in vaping initiation and satisfaction among U.S. adults. Addictive Behaviors, 106077. doi:10.1016/j.addbeh.2019.106077
  • This research was supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health (NIH) and the FDA Center for Tobacco Products (CTP) under Awards P50HL120163 and U54HL120163.


2018: Patterns of flavored e-cigarette use among adults vapers in the United States: an internet survey

  • Survey results submitted to the FDA
  • In conclusion, this cross-sectional study of a very large sample of adult US e-cigarette users, most of which were former smokers, identified the importance of non-tobacco flavors in e-cigarette use initiation and sustained use, and their contribution to smoking cessation and relapse prevention. *This information should be considered by regulators in order to avoid unintentional adverse effects of over-restrictive regulation on e-cigarette flavors.
  • PDF Version
  • Citation: Konstantinos Farsalinos, MD, MPH, Christopher Russell, PhD, George Lagoumintzis, PhD, Konstantinos Poulas, Submitted to: Docket No. FDA-2017 N-6565 for “Regulation of Flavors in Tobacco Products.”


2018: Changing patterns of first e-cigarette flavor used and current flavors used by 20,836 adult frequent e-cigarette users in the USA

  • Adult frequent e-cigarette users in the USA who have completely switched from smoking cigarettes to using e-cigarettes are increasingly likely to have initiated e-cigarette use with non-tobacco flavors and to have transitioned from tobacco to non-tobacco flavors over time. Restricting access to non-tobacco e-cigarette flavors may discourage smokers from attempting to switch to e-cigarettes.
  • PDF Version
  • Citation: Russell C, McKeganey N, Dickson T, Nides M. Changing patterns of first e-cigarette flavor used and current flavors used by 20,836 adult frequent e-cigarette users in the USA. Harm Reduct J. 2018 Jun 28;15(1):33. doi: 10.1186/s12954-018-0238-6. PMID: 29954412; PMCID: PMC6022703.
  • Acknowledgements: The authors are grateful to Julie Woessner and Alex Clark (Consumer Advocates for Smoke-free Alternatives Association), Stefan Didak and Danielle Bloss (Not Blowing Smoke), Gregory Conley (American Vaping Association), Cynthia Cabrera (Cating Group), and the Board of the Smoke-Free Alternatives Trade Association, without whose assistance this study would not have been possible. Fontem Ventures, a company that makes e-cigarettes, and a wholly owned subsidiary of Imperial Brands PLC provided funding for this study.


2018: Should flavours be banned in cigarettes and e-cigarettes? Evidence on adult smokers and recent quitters from a discrete choice experiment

  • A ban on flavoured e-cigarettes would likely increase the choice of cigarettes in smokers, the more harmful way of obtaining nicotine.
  • PDF Version
  • Citation:Buckell J, Marti J, Sindelar JLShould flavours be banned in cigarettes and e-cigarettes? Evidence on adult smokers and recent quitters from a discrete choice experimentTobacco Control 2019;28:168-175.
  • Acknowledgement: Research reported in this publication was supported by grant number P50DA036151 from the National Institute on Drug Abuse (NIDA) and FDA Center for Tobacco Products (CTP).


2017: Differences between Dual Users and Switchers Center around Vaping Behavior and Its Experiences Rather than Beliefs and Attitudes

  • To the extent that dual users substantially lower the number of cigarettes, they will reduce health risks from smoking. However, from a medical point of view, exclusive vaping is preferable to dual use;
  • Differences between dual users and switchers center around variables proximal to the vaping behavior and its experienced effects rather than hinging on more general vaping-related beliefs and attitudes.
  • After e-cig initiation, dual users decreased tobacco consumption by 82% and were low-to-moderately cigarette dependent.
  • The two groups (dual users and switchers) reported mostly using a flavor other than tobacco.
  • PDF Version
  • Citation: Adriaens K, Van Gucht D, Baeyens F. Differences between Dual Users and Switchers Center around Vaping Behavior and Its Experiences Rather than Beliefs and Attitudes. Int J Environ Res Public Health. 2017 Dec 23;15(1):12. doi: 10.3390/ijerph15010012. PMID: 29295483; PMCID: PMC5800112.


2016: Cigarette smoking and electronic cigarette vaping patterns as a function of e-cigarette flavourings

  • The findings suggest that adoption of e-cigarettes in smokers may influence smoking rates of people who smoke.
  • E-cigarette vaping rates are influenced by flavorings by people transistioning from smoking.
  • These findings have implications for the utility of e-cigarettes as a nicotine replacement device and for the regulation of e-cigarettes for harm reduction.
  • PDF Version
  • Citation: Litt MD, Duffy V, Oncken C. Cigarette smoking and electronic cigarette vaping patterns as a function of e-cigarette flavourings, Tobacco Control 2016;25:ii67-ii72.
  • Acknowledgement: Support for this project was provided by Grant 1 R01 DA036492 from the National Institute on Drug Abuse, and in part by General Clinical Research Center Grant M01-RR06192 from the National Institutes of Health.


2015: The Impact of Flavor Descriptors on Nonsmoking Teens’ and Adult Smokers’ Interest in Electronic Cigarettes

  • Nonsmoking teens’ interest in e-cigarettes was very low.
  • Adult smokers’ interest was significantly higher overall and for each flavor.
  • Teen interest did not vary by flavor, but adult interest did.
  • Past-30-day adult e-cigarette users had the greatest interest in e-cigarettes, and their interest was most affected by flavor.
  • Nonsmoking teens who had never tried e-cigarettes had the lowest interest in flavors, followed by adults who had never tried e-cigarettes
  • PDF Version
  • Citation: Saul Shiffman, PhD, Mark A Sembower, MS, Janine L Pillitteri, PhD, Karen K Gerlach, PhD, MPH, Joseph G Gitchell, BA, The Impact of Flavor Descriptors on Nonsmoking Teens’ and Adult Smokers’ Interest in Electronic Cigarettes, Nicotine & Tobacco Research, Volume 17, Issue 10, October 2015, Pages 1255–1262, doi: 10.1093/ntr/ntu333
  • Acknowledgement: This work was supported by NJOY, a company that markets electronic cigarettes, but does not make or sell any combustible tobacco products. All authors work for Pinney Associates and provide consulting services to GlaxoSmithKline Consumer Healthcare on their stop-smoking medications and to NJOY, Inc. on electronic nicotine delivery systems (ENDS). SS and JGG also own an interest in a novel nicotine medication in development. The study sponsor was involved in discussion of the study design, but had no role in study execution, data collection, data analysis, or writing of the manuscript, nor did the sponsor review the manuscript prior to submission.


2015: Preferred Flavors and Reasons for E-cigarette Use and Discontinued Use Among Never, Current, and Former Smokers

  • Never users had significantly lower prevalence of use of alcohol, marijuana, and other tobacco products (take less risks).
  • The most commonly reported reasons for e-cigarette use were “they might be less harmful than cigarettes” (77%); “they don’t smell” (77%); “they help people quit smoking” (66%); and “they cost less than other forms of tobacco” (62%); these reasons were more frequently endorsed by former smokers.
  • Among current e-cigarette users, the most commonly used flavor was fruit flavors (67%)
  • Over 90% of former cigarette smokers who were current e-cigarette users reported using e-cigarettes to quit smoking.
  • Over half of never smokers who are former e-cigarette users said they did not recently use e-cigarettes because they “just don’t think about it”, possibly indicating that addiction did not play a role in their use.
  • PDF Version
  • Citation: Berg CJ. Preferred flavors and reasons for e-cigarette use and discontinued use among never, current, and former smokers. Int J Public Health. 2016 Mar;61(2):225-36. doi: 10.1007/s00038-015-0764-x. Epub 2015 Nov 18. PMID: 26582009; PMCID: PMC4808473.
  • Acknowledgement: This research was supported by the National Cancer Institute (1K07CA139114-01A1; PI: Berg) and the Georgia Cancer Coalition (PI: Berg).


2013: Impact of Flavour Variability on Electronic Cigarette Use Experience: An Internet Survey

  • 4,618 participants were included in the analysis, with 4,515 reporting current smoking status (current vs. former smokers).
  • More than 90% were former smokers. The mean age was 40 years
  • At the time of participation, most commonly used flavors were fruits, followed by sweets.
  • Most participants (68.3%) were switching between flavours on a daily basis or within the day, with former smokers switching more frequently. More than half of the study sample mentioned that they like the variety of flavours and that the taste gets blunt from long-term use of the same flavour. The average score for importance of flavours variability in reducing or quitting smoking was 4 (“very important”). Finally, the majority of participants stated that restricting variability of flavours would make the EC experience less enjoyable while almost half of them answered that it would increase craving for tobacco cigarettes and would make reducing or completely substituting smoking less likely.
  • The results of this survey indicate that EC liquid flavourings play a major role in the overall experience of dedicated users and support the hypothesis that they are important contributors in reducing or eliminating smoking consumption.
  • PDF Version
  • Citation: Farsalinos, K., 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. doi:10.3390/ijerph10127272
  • Acknowledgement: No funding was received for this study.

Nicotine Levels

2020: Might limiting liquid nicotine concentration result in more toxic electronic cigarette aerosols?

  • Thus, if users seek a given nicotine yield, regulatory limits on nicotine concentration may have the unintended consequence of increasing exposure to aerosol and respiratory toxicants. This outcome demonstrates that attempting to control ECIG nicotine yield by regulating one factor at a time may have unintended health effects and highlights the need to consider multiple factors and outcomes simultaneously when designing regulations..
  • PDF Version


2020: Reported patterns of vaping to support long-term abstinence from smoking: a cross-sectional survey of a convenience sample of vapers

  • Qualitative research suggests e-cigarettes can meet many of the needs of ex-smokers by substituting physical, psychological, social, cultural and identity-related aspects of tobacco addiction.
  • According to a time-series analysis of data from the Smoking Toolkit study, in which repeated cross-sectional surveys are conducted with a representative sample of households in England, increasing prevalence of e-cigarette use in current smokers was predictive of higher success rates of quit attempts.
  • Most participants were self-reported long-term abstinent smokers (86.3%).
  • Those who start on a low self-reported nicotine e-liquid concentration (strength) will be more likely to relapse to tobacco smoking than those starting on a higher nicotine e-liquid, after controlling for cigarettes per day (CPD) before cessation.
  • Results suggest a change in flavor choices over the course of vaping initiation and uptake. There was a reduction in the proportion of people using a tobacco flavor, and increase in the proportion using a fruit/sweet/food flavor, from initial to current flavor choice
  • According to the 2017 ASH-A survey, among current users, fruit flavors were the most popular.
  • PDF Version
  • Citation: Gentry, S.V., Ward, E., Dawkins, L. et al. Reported patterns of vaping to support long-term abstinence from smoking: a cross-sectional survey of a convenience sample of vapers. Harm Reduct J 17, 70 (2020). doi:10.1186/s12954-020-00418-8
  • Acknowledgement: This research was funded by Cancer Research UK (CRUK), Grant Number C54889/A22732.


2016: Protocol proposal for, and evaluation of, consistency in nicotine delivery from the liquid to the aerosol of electronic cigarettes atomizers: regulatory implications

  • Electronic cigarettes that use tank‐type atomizers appear to deliver nicotine in more consistent quantities (within the acceptable limits for medicinal nebulizers and similar to the nicotine inhaler) than electronic cigarettes that use cartomizers.
  • The protocol for testing nicotine delivery consistency described in this paper could be used effectively for regulatory purposes.
  • PDF Version


2013: Evaluating Nicotine Levels Selection and Patterns of Electronic Cigarette use in a Group of “Vapers” Who Had Achieved Complete Substitution of Smoking

  • Nicotine levels appear to play an important role in achieving and maintaining smoking cessation in the group of motivated subjects studied. High nicotine-containing liquids were used while few mild and temporary side effects were reported. Proposals about regulation should consider the pragmatic use patterns of ECs, especially in consumers who have completely substituted smoking.
  • 42% of participants reported quitting smoking during the first month of EC use.
  • Liquids with nicotine concentration >15 mg/mL were used by 74% of users at initiation of EC use, while 16.2% had to increase the initial nicotine levels in order to achieve complete smoking abstinence.
  • 64.9% reported that from the time of smoking cessation to the time of the interview (8 months median duration of EC use) they reduced the nicotine concentration they were consuming.
  • The vast majority of participants reported better exercise capacity and improved olfactory and gustatory senses.
  • Perceived EC dependency was significantly lower compared to smoking.
  • PDF Version


2013: Nicotine levels in electronic cigarettes

  • E-cigarettes (ECs) generate vapor that contains nicotine, but EC brands and models differ in their efficacy and consistency of nicotine vaporization. In ECs, which vaporize nicotine effectively, the amount inhaled from 15 puffs is lower compared with smoking a conventional cigarette.
  • PDF Version


Older Adults

2021: Paper: Ignoring our elders: tobacco control’s forgotten health equity issue

  • BMJ Tobacco Control


2019: Article: Older Smokers Are the Forgotten Victims of Our Vaping Wars

  • Filter Magazine


2018: Power Point: Rethinking nicotine across the lifespan: What about the older smoker?

  • GFN: Annie Kleykamp, PhD


2017: Article: Some Older Smokers Turn to Vaping. That May Not Be a Bad Idea.

  • NY Times


2017: Article: Vaping Becoming Popular Among Older Smokers

  • AARP


2011: Paper: The Older Smoker

  • JAMA


Personal Testimonies from people who used to smoke

All Years: Video Collection: Golden Oldies Capitol Tours

  • People who used to smoke share how long they smoked and what flavors helped them to quit smoking.


All Years: Collection 13,000+ Testimonies: CASAA - REAL PEOPLE. REAL STORIES.

  • Online submissions of personal testimonies by people who switched from smoking to harm reduction products.


Quitting Smoking / Preventing Relapse

See our page with a collection of studies showing that many people successfully quit smoking with the use of these products.

Race / Ethnic / Socioeconomic / Education

2020: Inequalities, harm reduction and non-combustible nicotine products: a meta-ethnography of qualitative evidence

  • The review only identified studies exploring the attitudes of socioeconomically disadvantaged smokers towards NCNP (non-combustible nicotine products) for harm reduction or cessation purposes (i.e. we did not identify any relevant studies of more advantaged socioeconomic groups).
  • Using a lines-of-argument meta-ethnographic approach, we identified a predominantly pessimistic attitude to NCNP for harm reduction or cessation of smoking due to:
    • wider circumstances of socioeconomic disadvantage;
    • lack of a perceived advantage of alternative products over smoking;
    • and a perceived lack of information about relative harms of NCNP compared to smoking.
  • Optimistic findings, although fewer, suggested the potential of NCNP being taken up among smokers experiencing socioeconomic disadvantage.
  • PDF Version
  • Citation: Lucherini M, Hill S, Smith K. Inequalities, harm reduction and non-combustible nicotine products: a meta-ethnography of qualitative evidence. BMC Public Health. 2020;20(1):943. Published 2020 Jun 15. doi:10.1186/s12889-020-09083-9
  • Acknowledgement: The review is part of a project funded by Cancer Research UK. The award number is: C55561/A21553.


2019: Socioeconomic Disparities in Electronic Cigarette Use and Transitions from Smoking

  • Furthermore, more educated smokers are more likely to switch to exclusive e-cigarette use than less educated smokers.
  • Such differential switching may exacerbate socioeconomic disparities in smoking-related morbidity and mortality, but lower the burden of tobacco-related disease.
  • PDF Version
  • Citation: Friedman, A. S., & Horn, S. J. L. (2018). Socioeconomic Disparities in Electronic Cigarette Use and Transitions from Smoking. Nicotine & Tobacco Research. doi:10.1093/ntr/nty120
  • Acknowledgement: This work was not supported by outside funding.


2019: Vaping patterns, nicotine dependence and reasons for vaping among American Indian dual users of cigarettes and electronic cigarettes

  • The ten-item Penn State Dependence Index (PSDI) suggested greater dependence on smoking than vaping
  • The most common reasons for vaping were to reduce smoking (79%), enjoyment of flavors (78%), and ability to vape where smoking is not allowed (73%). Perceptions of less harm to others (69%) or to self were the next most common (65%). Fewer than half used ECs to reduce stress, for affordability, or because others used them.
  • PDF Version
  • Citation: Rhoades DA, Comiford AL, Dvorak JD, Ding K, Hopkins M, Spicer P, Wagener TL, Doescher MP. Vaping patterns, nicotine dependence and reasons for vaping among American Indian dual users of cigarettes and electronic cigarettes. BMC Public Health. 2019 Sep 2;19(1):1211. doi: 10.1186/s12889-019-7523-5. PMID: 31477072; PMCID: PMC6721166.
  • Acknowledgement: Grants from the National Cancer Institute of the National Institutes of Health (P20CA202921 to University of Oklahoma, and 5P20CA202923 to Cherokee Nation) supported this study.


2019: Effect of Electronic Cigarettes on Smoking Reduction and Cessation in Korean Male Smokers: A Randomized Controlled Study

  • In our study, the effect of e-cigarettes on smoking cessation was similar compared with that of nicotine gum, a well-documented NRT. In addition, e-cigarettes were well tolerated by the study population. Therefore, the use of e-cigarettes as an NRT may be considered for smoking-cessation purposes.
  • PDF Version
  • Citation: Effect of Electronic Cigarettes on Smoking Reduction and Cessation in Korean Male Smokers: A Randomized Controlled Study; Seung-Hwa Lee, Sang-Hyun Ahn, Yoo-Seock Cheong; The Journal of the American Board of Family Medicine Jul 2019, 32 (4) 567-574; DOI: 10.3122/jabfm.2019.04.180384
  • Acknowledgement: No outside funding


2018: Socioeconomic and Racial/Ethnic Differences in E-Cigarette Uptake Among Cigarette Smokers: Longitudinal Analysis of the Population Assessment of Tobacco and Health (PATH) Study

  • Compared with non-Hispanic Whites, non-Hispanic Black, and Hispanics were less likely to become exclusive e-cigarette users
  • Low-income smokers were less likely than higher-income smokers to become exclusive e-cigarette users
  • Black, Hispanic, and low-income smokers were more likely to believe e-cigarettes are more harmful than cigarettes and to have positive tobacco-related social norms.
  • Results of this study show that the exclusive use of e-cigarettes is more prevalent in higher-income and White smokers. Our data suggest that higher-income and White smokers may be more likely to use e-cigarettes as a means to quit combustible cigarettes compared with low-income and racial/ethnic minority smokers. These findings suggest that sociodemographic differences in e-cigarette uptake and use patterns may contribute to widening disparities in cigarette smoking.
  • PDF Version
  • Citation: Harlow AF, Stokes A, Brooks DR. Socioeconomic and Racial/Ethnic Differences in E-Cigarette Uptake Among Cigarette Smokers: Longitudinal Analysis of the Population Assessment of Tobacco and Health (PATH) Study. Nicotine Tob Res. 2019;21(10):1385-1393. doi:10.1093/ntr/nty141
  • Acknowledgement: Research was supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health and the Center for Tobacco Products under Award Number P50HL120163.


2016: Racial/Ethnic Differences in Electronic Cigarette Use and Reasons for Use among Current and Former Smokers: Findings from a Community-Based Sample

  • This study found more similarities than differences among Whites, African Americans/Blacks, and Hispanics with a history of tobacco smoking.
  • African Americans/Blacks were significantly less likely to report ever-use compared to Whites and Hispanics (50% vs. 71% and 71%, respectively; p < 0.001).
  • African American/Black ever users were more likely to report plans to continue using e-cigarettes compared to Whites and Hispanics (72% vs. 53% and 47%, respectively, p = 0.01).
  • African American/Black participants were more likely to use e-cigarettes as a cessation aid compared to both Whites (p = 0.03) and Hispanics (p = 0.48)
  • White participants were more likely to use e-cigarettes to save money compared to Hispanics (p = 0.02).
  • PDF Version
  • Citation: Webb Hooper M, Kolar SK. Racial/Ethnic Differences in Electronic Cigarette Use and Reasons for Use among Current and Former Smokers: Findings from a Community-Based Sample. Int J Environ Res Public Health. 2016;13(10):1009. Published 2016 Oct 14. doi:10.3390/ijerph13101009
  • Acknoledgement: We thank the Sylvester Comprehensive Cancer Center at the University of Miami for funding this study and Case Comprehensive Cancer Center for providing funds for open access publication.



Regulations (not including taxes)

2021: Regulation of e-cigarette flavours – a response

  • Testimony in Netherlands pertaining to a potential flavour / flavor ban. This document responds to the proposed Decree of the State Secretary for Health, Welfare and Sport on the regulation of e-cigarette flavours in the Netherlands.
  • Signed by 24 experts from around the world
  • Covers 12 key points
    • Sets conflicting objectives and takes a “war on drugs” approach to nicotine.
    • Adopts false and misleading claims about the risks of e-cigarettes.
    • Draws on irrelevant information about an outbreak of lung injuries in North America.
    • Misunderstands “dual-use”.
    • Asserts a “gateway effect” but there is more likely to be a diversion away from smoking.
    • Takes a simplistic approach to youth risk behaviours and fails to demonstrate benefits to adolescent public health.
    • Ignores perverse consequences of prohibition, even though these are foreseeable.
    • Fails to show benefits for adolescents or address concerns it may cause harm to young people.
    • Ignores the harmful effects of a vaping flavour ban on adults.
    • Creates regulatory protection for the cigarette trade.
    • Violates important regulatory principles, including those underpinning the European Union internal market.
    • Proposes an illiberal policy and fails to recognise a major global public health opportunity.
  • Acknowledgement: We confirm that signatories report no conflicts with respect to FCTC Article 5.3 and no financial conflicts of interest with respect to tobacco or e-cigarette companies under the International Committee of Medical Journal Editors (ICJME) reporting standard.


2020: Are E-Cigarette Regulations Jeopardizing the Public Health?

  • The demonization of e-cigarettes in the U.S. is counterproductive. As part of a tobacco harm reduction strategy, the potential public health benefits from e-cigarettes are substantial. Opposition to e-cigarettes, often fueled by misleading information, curbs their use as a smoking cessation aid by millions of adults.
  • E-cigarettes are far less harmful than combustible cigarettes and constitute one of the most common -- and effective -- smoking cessation aids. Overzealous or poorly designed restrictions on vaping, combined with misleading information about e-cigarettes’ true health risks, are deterring smokers from pursuing a potentially life-saving alternative.
  • If cigarette use were largely replaced by vaping over a 10-year period in the U.S., it would prevent as many as 6.6 million premature deaths.
  • A report by a government agency, the Public Health of England, an agency of England’s Department of Health and Social Care, reported that most consumers who vape do so in order to stop smoking.
  • The doses of toxins contained in e-cigarettes are typically hundreds or thousands of times lower than in regular cigarettes. While non-smokers would be ill-advised to take up vaping, smokers could reap significant health benefits from switching to e-cigarettes.
  • Underage vaping by nonsmokers is rare, which supports the correlation that the rise in vaping has led to a decline in smoking among teens.
  • Not only does the hysteria surrounding e-cigarettes endanger smokers and jeopardize public health, it also undermines the credibility of health authorities on other important issues like the coronavirus and vaccines. The American public should be told the truth about e-cigarettes.
  • Too often, policymakers have acted without carefully weighing the costs and benefits of their actions. Knee-jerk opposition to e-cigarettes, often fueled by misleading information, curbs their use as a smoking cessation aid by millions of adults.
  • Acknowledgement: Liam Sigaud, Dr. Krisztina Pusok, Janson Q. Prieb and Steve Pociask are with the American Consumer Institute, Center for Citizen Research, a nonprofit educational and research organization. A special thanks to Guy Bentley, Director of Consumer Freedom Research at the Reason Foundation, for his helpful comments. For more information about the Institute, visit www.TheAmericanConsumer.Org or follow us on Tweeter @ConsumerPal.


2020: A rational approach to e-cigarettes: challenging ERS policy on tobacco harm reduction

  • We believe that blanket opposition to e-cigarettes is misguided and will lead to a number of important consequences that are adverse to health.
    • First, smokers who would otherwise have quit smoking by switching to a lower risk product will continue to smoke, and die prematurely from cancer, cardiovascular and respiratory disease.
    • Second, people who have successfully switched to vaping may relapse to smoking if they come to believe that there is no health benefit from vaping, and thus increase their risk of avoidable morbidity and premature death.
    • Third, the pursuit of arguments that vaping can’t help people to quit smoking, in the face of clear evidence that it does, risks undermining public trust in science.
  • PDF Version
  • Citation: A rational approach to e-cigarettes: challenging ERS policy on tobacco harm reduction, John Britton, Jacob George, Linda Bauld, Sanjay Agrawal, John Moxham, Deborah Arnott, Ann McNeill, Nicholas S. Hopkinson - European Respiratory Journal May 2020, 55 (5) 2000166; DOI: 10.1183/13993003.00166-2020


2020: Vape shop owners/managers’ opinions about FDA regulation of e-cigarettes

  • Vape shop owners/managers reported:
    • 1) entering the industry with positive intentions for their customers;
    • 2) training their personnel to adhere to regulations and provide good customer service; and
    • 3) significant concerns about the impact of FDA regulations. With regard to the latter, participants reported mistrust of the intentions of the FDA regulations, financial implications of the regulations (particularly for small businesses), difficulty understanding and interpreting the regulations, insufficient evidence to support the regulations, negative impact on customer service, negative impact on product offerings and product innovation/advancement, and negative implications of flavor bans and/or restrictions on sale of flavors.
  • PDF Version
  • Citation: Carla J Berg, PhD, MBA, Dianne C Barker, MHS, Steve Sussman, PhD, Betelihem Getachew, MPH, Kim Pulvers, PhD, MPH, Theodore L Wagener, PhD, Rashelle B Hayes, PhD, Lisa Henriksen, PhD, Vape Shop Owners/Managers’ Opinions About FDA Regulation of E-Cigarettes, Nicotine & Tobacco Research, Volume 23, Issue 3, March 2021, Pages 535–542, https://doi.org/10.1093/ntr/ntaa138
  • Acknowledgement: This work was supported by the National Cancer Institute (R01CA215155-01A1; PI: Berg).


2019: E-cigarettes: Comparing the Possible Risks of Increasing Smoking Initiation with the Potential Benefits of Increasing Smoking Cessation

  • Potential life-years gained as a result of vaping-induced smoking cessation are projected to exceed potential life-years lost due to vaping-induced smoking initiation. These results hold over a wide range of plausible parameters
  • Our analysis strongly suggests that the upside health benefit associated with e-cigarettes, in terms of their potential to increase adult smoking cessation, exceeds their downside risk to health as a result of their possibly increasing the number of youthful smoking initiators. Public messaging and policy should continue to strive to reduce young people's exposure to all nicotine and tobacco products. But, they should not do so at the expense of limiting such products' potential to help adult smokers to quit.
  • PDF Version
  • Citation: Warner, K. E., & Mendez, D. (2018). E-cigarettes: Comparing the Possible Risks of Increasing Smoking Initiation with the Potential Benefits of Increasing Smoking Cessation. Nicotine & Tobacco Research. doi:10.1093/ntr/nty062
  • Acknowledgements: This work was not supported by any external funding.


2019: Young adult dual combusted cigarette and e-cigarette users’ anticipated responses to hypothetical e-cigarette market restrictions

  • Hypothetical regulations resulted in reported intentions to reduce EC (e-cigarette) use and increase CC (combustible cigarette) use; the greatest impact was found for restrictions regarding e-liquid nicotine content, followed by flavor
  • This work provides preliminary evidence that restrictive regulations regarding key EC characteristics may increase intentions to increase CC use among young adult dual EC and CC users.
  • PDF Version
  • Citation:: Lauren R. Pacek, Olga Rass, Maggie M. Sweitzer, Jason A. Oliver & F. Joseph McClernon (2019): Young adult dual combusted cigarette and e-cigarette users’ anticipated responses to hypothetical e-cigarette market restrictions, Substance Use & Misuse, DOI:10.1080/10826084.2019.1626435
  • Acklnowledgement: This work was supported by the National Institutes of Health (K01DA043413, K23DA039294, and K23DA042898). The funding source had no other role other than financial support.


2017: Does the Regulatory Environment for E-Cigarettes Influence the Effectiveness of E-Cigarettes for Smoking Cessation?

  • This study shows that in a less restrictive EC (E-Cigarette) regulatory environment, use of ECs during a quit attempt facilitates, but in a more restrictive environment it inhibits, short-term sustained abstinence. The findings underscore the need for careful consideration on how best to regulate this emerging product so that EC benefits for smoking cessation are maximized and its risks to public health are minimized.
  • PDF Version
  • Citation: Hua-Hie Yong, PhD, Sara C Hitchman, PhD, K Michael Cummings, PhD, Ron Borland, PhD, Shannon M L Gravely, PhD, Ann McNeill, PhD, Geoffrey T Fong, PhD, Does the Regulatory Environment for E-Cigarettes Influence the Effectiveness of E-Cigarettes for Smoking Cessation?: Longitudinal Findings From the ITC Four Country Survey, Nicotine & Tobacco Research, Volume 19, Issue 11, November 2017, Pages 1268–1276, https://doi.org/10.1093/ntr/ntx056
  • Acknowledgement: KMC has received grant funding from Pfizer, Inc. to study the impact of a hospital based tobacco cessation intervention and also has served as an expert witness in litigation filed against the tobacco industry. Ethical Approval: All waves of the study have received ethical approval from the relevant research ethics committee at the Cancer Council Victoria (Australia), Medical University of South Carolina (USA), University of Waterloo (Canada) and the University of Strathclyde (UK).


2016: A Framework for Evaluating the Public Health Impact of E-cigarettes and Other Vaporized Nicotine Products

  • The primary aim of tobacco control policy should therefore be to discourage cigarette use while providing the means for smokers to more easily quit smoking, even if that means switching for some time to VNPs (vaporized nicotine products) rather than quitting all nicotine use. Countries whose policies discourage VNP use run the risk of neutralizing a potentially useful addition to methods of reducing tobacco use.
  • PDF Version
  • Citation: Levy, D. T., Cummings, K. M., Villanti, A. C., Niaura, R., Abrams, D. B., Fong, G. T., & Borland, R. (2016). A framework for evaluating the public health impact of e-cigarettes and other vaporized nicotine products. Addiction, 112(1), 8–17. doi:10.1111/add.13394
  • Acknowledgment: Funding was received from the Food and Drug Administration through the National Institute on Drug Abuse under grant 1R01DA036497-01.
  • Article: Public health benefits of e-cigarette use tend to outweigh the harms, new study says
  • Article: Top tobacco control experts to FDA: Studies of e-cigs suggest more benefit than harm


2015: Ethical issues raised by a ban on the sale of electronic nicotine devices

  • Respect for autonomy: prohibiting ENDS infringes on smokers’ autonomy to use a less harmful nicotine product while inconsistently allowing individuals to begin and continue smoking cigarettes.
  • Non‐maleficence: prohibition is supposed to prevent ENDS recruiting new smokers and discouraging smokers from quitting. It also perpetuates harm by preventing addicted smokers from using a less harmful nicotine product.
  • Beneficence: ENDS could benefit addicted smokers by reducing their health risks if they use them to quit and do not engage in dual use.
  • Distributive justice: lack of access to ENDS disadvantages smokers who want to reduce their health risks. Different national policies create inequalities in the availability of products to smokers internationally.
  • PDF Version
  • Citation: Hall, W., Gartner, C., & Forlini, C. (2015). Ethical issues raised by a ban on the sale of electronic nicotine devices. Addiction, 110(7), 1061–1067. doi:10.1111/add.12898
  • Acknowledgement: C.G. is supported by an NHMRC Career Development Award. C.F. is supported by funding from the Australia Research Council for research on the use of stimulant drugs as cognitive enhancers. We would like to thank Sarah Yeates for her assistance in preparing this paper for publication.


Taxes

See this page: "ENDS Taxes"

  • Contains studies, articles, news, videos, etc. about taxing vapor products.



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Implementation of smokefree prisons in Scotland: findings from the Tobacco in Prisons (TIPs) study

Expression of Key Inflammatory Proteins Is Increased in Immune Cells From Tobacco Cigarette Smokers But Not Electronic Cigarette Vapers: Implications for Atherosclerosis

Can E-Cigarettes and Pharmaceutical Aids Increase Smoking Cessation and Reduce Cigarette Consumption? Findings From a Nationally Representative Cohort of American Smokers

Patients with lung cancer: Are electronic cigarettes harmful or useful?

Based on current knowledge, for patients with lung or other forms of cancer who would otherwise continue to smoke, e-cigarettes offer an alternative way to quit smoking while they undergo medical treatment. The option to switch to e-cigarettes should be considered by healthcare practitioners with patients with cancer who would otherwise continue to smoke.


Electronic cigarette use among patients with cancer: Reasons for use, beliefs, and patient-provider communication

Patients with cancer who use e-cigarettes have positive attitudes toward these devices and use them to aid in smoking cessation.

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