E-cigarettes for smoking cessation: What do we know?

The Bottom Line

  • The use of tobacco is a pressing public health concern and is seen as an "epidemic."
  • Tobacco kills 1 in 2 users. The majority of those who use tobacco smoke cigarettes, but quitting is no easy feat.
  • Current evidence shows that e-cigarettes containing nicotine can be more effective in helping people to quit smoking compared to other smoking cessation strategies, but more research is needed to confirm these results.   
  • Looking to quit smoking? Discuss this health goal with your health care team. Together you can assess the different support tools available, their pros and cons, and develop a quit plan that optimizes your chances of success.  

We frequently refer to a variety of infectious and chronic diseases—such as HIV, diabetes, and obesity—as "epidemics." The use of this terminology highlights the reach and impact of these diseases and pushes us to find treatments and preventative strategies that address them. Tobacco, which kills 1 in 2 of its users, has also been termed an “epidemic” and is deemed one of the greatest public health hazards seen to date. Smoking cigarettes is the most widespread method of tobacco use (1). As such, avoiding smoking altogether or quitting if you already smoke is highly recommended by experts.  

But, some things are easier said than done... even when we are really motivated to achieve them. Quitting smoking happens to be one of those difficult things. In fact, research shows that among those who do not utilize support strategies when they attempt to quit, approximately 50% will be unable to stay smoke free for a week, while over 95% will be unable to stay smoke free for one year (2;3). This means that safe and effective quitting aids and supports are important for achieving success.  

In recent years, there have been times when the news headlines have been dominated by conversations about electronic cigarettes (aka e-cigarettes) or "vapes." These tobacco free handheld devices, which are generally powered by a battery, work by heating up a liquid to produce an often-flavoured vapour that forms into an aerosol. This aerosol is then breathed in and out—an action known as vaping. Some e-cigarettes contain nicotine, while others do not (2;4;5). Research and news articles have dissected the use of e-cigarettes in general and as tools for smoking cessation, how they are marketed, possible health concerns, and their potential to roll back significant public health advances related to tobacco control.

With so much controversy and uncertainty surrounding e-cigarettes, it is important to understand where the best available evidence currently stands on their use as smoking cessation aids.

What the research tells us

A comprehensive systematic review, recently updated (November 2022), investigated whether e-cigarettes can help people who smoke quit, and whether they are safe to use for this purpose.

Ultimately, the review reported:

  1. based on six studies, high certainty that those receiving nicotine e-cigarettes had higher quit rates for at least six months compared to those receiving nicotine replacement therapy,
  2. based on five studies, moderate certainty that those receiving nicotine e-cigarettes had higher quit rates for at least six months compared to those receiving nicotine-free e-cigarettes, and 
  3. based on seven studies, very low certainty that those receiving nicotine e-cigarettes had higher quit rates for at least six months compared to those receiving no support or behavioural support alone.  

While 78 studies are included in this review, only 10 were assessed to be of high quality, with 50 being judged to have serious limitations. The authors note in their conclusions that for the small number of studies, particularly for outcomes #2 and #3 above, the findings are imprecise, reducing the certainty of those effects. However, the authors also note that further studies are underway; so, it is possible these results may change as new results emerge.

Generally, there were no substantial differences in the number of side effects that occurred between those using nicotine e-cigarettes and those using other quitting strategies, although there continues to be a limited number of rigorous studies evaluating these outcomes, and these results may change as new studies emerge. It is also important to note that there is a lack of data on long-term impacts.

If you smoke but want to quit, speak with your health care team about all quitting aids and supports that are currently available and recommended. Ask about the pros and cons and get help with developing a plan that you can adhere to and will increase your chance of success. Good luck!

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Author Details


  1. World Health Organization. Tobacco. [Internet] 2022. [cited September 2022]. Available from https://www.who.int/news-room/fact-sheets/detail/tobacco
  2. Hartmann-Boyce J, Lindson N, Butler AR, et al. Electronic cigarettes for smoking cessation. Cochrane Database Syst Rev. 2022; 11:CD010216. doi: 10.1002/14651858.CD010216.pub7.
  3. Hughes JR, Keely J, Naud S. Shape of the relapse curve and long-term abstinence among untreated smokers. Addiction. 2004; 99(1):29-38.
  4. Hartmann-Boyce J, McRobbie H, Butler AR, et al. Electronic cigarettes for smoking cessation. Cochrane Database of Syst Rev. 2021; 9:CD010216. doi: 10.1002/14651858.CD010216.pub6.
  5. Government of Canada. About vaping. [Internet] 2022. [cited September 2022]. Available from https://www.canada.ca/en/health-canada/services/smoking-tobacco/vaping.html

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