Electronic cigarettes for smoking cessation (Review) (2024)

Stopping smoking lowers the risk of cancer, heart attacks and many other diseases. Many people find it difficult to stop smoking. We wanted to find out if using e-cigarettes could help people to stop smoking, and if people using them for this purpose experience any unwanted effects.
We searched for studies that looked at the use of e-cigarettes for stopping smoking.
We looked for randomized controlled trials, in which the treatments people received were decided at random. This type of study usually gives the most reliable evidence about treatment effects. We also looked for studies in which everyone received e-cigarette treatment. We also included studies that gave smokers e-cigarettes and monitored their health even if there was no randomised group, because such studies can contribute to our understanding of the health effects of using EC.
We were interested in finding out:
- how many people stopped smoking for at least six months; and
- how many people had unwanted effects, reported on after at least one week of use.
Search date: We included evidence published up to 1st July 2023.
We found 88 studies which included 27,235 adults who smoked. The studies compared e-cigarettes with:
- nicotine replacement therapy, such as patches or gum;
- varenicline (a medicine to help people stop smoking);
- e-cigarettes without nicotine;
- heated tobacco (products designed to heat tobacco to a high enough temperature to release vapour, without burning it or producing smoke; these differ from e-cigarettes because they heat tobacco leaf/sheet rather than a liquid);
- other types of nicotine-containing e-cigarettes (e.g. pod devices, newer devices);
- behavioural support, such as advice or counselling; or
- no support for stopping smoking.
Most studies took place in the USA (38 studies), the UK (19), and Italy (9).
KEY MESSAGES:
Nicotine e-cigarettes can help people to stop smoking for at least six months. Evidence shows they work better than nicotine replacement therapy, and probably better than e-cigarettes without nicotine.
They may work better than no support, or behavioural support alone, and they may not be associated with serious unwanted effects.
However, we still need more evidence, particularly about the effects of newer types of e-cigarettes that have better nicotine delivery than older types of e-cigarettes, as better nicotine delivery might help more people quit smoking.