Electronic cigarettes and the difficulty of scientifically proving their effectiveness

January 2019 is a historic date for vaping since, for the first time, the ECSS (Economic, Social and Environmental Council) officially recognised electronic cigarettes as effective tools for smoking cessation1. It also recommends the setting up of training courses on the operation of equipment intended for health professionals to promote its use with smokers. It is an important symbol which should mark a turning point in vaping in France.

For almost a decade electronic cigarettes have been used by smokers to slow down or completely stop their consumption of tobacco cigarettes. Nevertheless, the effectiveness of vaping remains difficult to prove from a scientific point of view.

When the compilations of articles are examined, it is not rare to still find conclusions such as “the effectiveness of e-cigarettes as tools for smoking cessation is currently uncertain due to the lack of data or to the quality of the data collected during clinical trials2-4. While other studies on the contrary confirm that the daily use of an electronic cigarette by a smoker would increase their chances if quitting from 6 to 15%, compared to other nicotinic substitutes5-6.

This ambivalence is explained in part by the difficulty in comparing the statistical analysis with the reality on the ground. Indeed, clinical studies intended to observe user behaviour have to comply with a very strict management protocol. Vapers then cannot choose or vary the equipment or the liquid which are often required for the study. One of the main advantages of vaping lies in its modular scope. Actually, consumers choose their e-cigarette and e-liquid according to their needs. These conditions are not compatible with the standard framework of a clinical trial.

Another difficulty is also added to the lack of realism of the clinical data, which is the fast changing character of this sector. The studies produced quickly become obsolete as the equipment and habits of consumers change rapidly. For example take those carried out in 2011 which are no longer representative because the vaporisation equipment has clearly improved in recent years. Today it offers greater modulation enabling better delivery of the nicotine (more and faster) and thus better chances of stopping.

Moreover, in many cases, studying the effects of e-cigarettes on smoking cessation is limited to the first 3 months after stopping cigarettes, which is insufficient.

Questions should also be asked about the influence that the media’s special treatment of vaping can have with its users. The image of “electronic cancer” is in particular conveyed by some papers7 which do not hesitate to confuse tobacco with nicotine having as consequence the degradation of the image of the e-cigarette by a significant part of the French population. These received ideas can eventually create doubts on its effectiveness as a tool of smoking cessation. However, while this disinformation can lead to mistrust with smokers and their acquaintances, it should only have a very limited effect with vapers who have already passed this phase of discovery.

Despite these many brakes, English scientists8 have recently carried out a study on the effects of smoking cessation with 880 people over one year. Half used e-cigarettes (rechargeable, free choice of e-liquids), the others consumed other nicotinic substitutes (combination of several substitutes for 88% of the candidates). In each of the categories, medical support was offered. The results demonstrate the superiority of the electronic cigarette over the other substitutes with a success percentage after one year of 18% for the e-cigarette against 8% for the “classic” substitutes (patchs, gums, spray…).

Smoked cigarettes: a hard drug with multiple facets

In 2017, a review9 summarising the conclusions of more than 2700 studies on the impact of smoking dependency, comes to the conclusion that 70% of people having tried tobacco cigarettes at least once are led on to become daily smokers.

Smoking dependency stems not solely from a physical dependency on nicotine. There is pharmacological dependency, but also psychological and social: The speed of assimilation of nicotine, the gestures (handling, contact of the cigarette with the mouth, inhalation and exhalation of the smoke, etc.), its social role (coffee breaks, parties, etc.).  All these habits are anchored in the smoker. So, to succeed in quitting, all these things have to be satisfied. It is not enough to provide sufficient doses of nicotine to their brain; it is also necessary to answer the smoker’s other needs such as holding something in the hand or exhaling vapour (or smoke). Furthermore, smoking dependency also raises an individual or personal dimension. The craving for a cigarette can be triggered in several ways with smokers and each of them will react differently according to the environmental, social, and affective context…  Finally, it can be seen that there are as many smoking dependencies as there are smokers. It should be understood that this dependency is extremely powerful but difficult to study from a scientific point of view. Moreover, the craving for a cigarette can occur even with people who have stopped for several years. Pr. B. Dautzenberg, former President of the French Office for smoking prevention summarised the situation very well: “a former smoker never becomes a non-smoker, they will always remain an ex-smoker”.

Faced with this observation, the electronic cigarette has real interest. Thanks to its modular aspect, it comes at the head of effective products for smoking cessation because it helps alleviate almost all the components of dependency caused by the consumption of tobacco cigarettes.

Towards easier smoking cessation?

Detractors of e-cigarettes stress that vaping with a low level or 0 mg/ml of nicotine does not ensure total cessation because the gestural addiction remains. If one quits tobacco, it is not necessarily the case for nicotine and still less the psychological dimension of the act. The dependency remains and anti-vapers condemn its use because it does not (still) enable the complete cessation of all types of nicotine products. It could also risk leaving the door open to another return to tobacco.

In an English study10, the scientists sought to observe the causes of cessation failure and compared the results of vaping products with those of other nicotinic substitutes. It appears that for the e-cigarette, the undesirable side effects (headache, cough, etc.) are greater at the start than for other methods. But this observation tends to be reversed after several weeks use. Indeed, the vaper has meanwhile appropriated the tool and has adapted their consumption, which is impossible with the use of a patch for example. Moreover, in certain specific cases, the vaper be allowed to smoke a tobacco cigarette, nevertheless without consuming them again regularly. The reasons can be varied such as equipment problems (discharged battery, out of e-liquid) or social factors (being with smokers). These “allowed behavioural deviations”, fairly recent findings in the history of studying smoking cessation, are easier to live with than a relapse (both physically and psychologically). In this study, Dr Notley10 thus confirms that “For former smokers, vaping offers a pleasure, that is viable pharmacologically, but also socially and psychologically; a tobacco substitute option which powerfully modifies the risk of relapse”.

What now?

In so far as e-cigarettes are officially recognised as a smoking cessation tool, doctors should be trained and the public better informed! This would allow smokers, who want to stop smoking, to see vaping as a real effective solution for quitting tobacco cigarettes. It is now necessary for the media, which for many remain the great influencers of public opinion, to recognise this change and that they alter their approach to e-cigarettes. This is hopeful because we have already seen for some time that a form of objectivity is emerging in the French press. A survey11 for France Info and Le Figaro and carried out on the occasion of the World No Smoking Day in May 2018 demonstrated that vaping had become the most popular smoking cessation tool with smokers in France.


1 : Conseil économique, social et environnemental, 2019 https://www.lecese.fr/sites/default/files/pdf/Avis/2019/2019_02_addictions.pdf

2 : Hartmann-Boyce et al, 2016

3 : El Dib et al, 2017

4 : Kalkhoran et al, 2016

5 : Benmarhnia et al, 2018

6 : Giovenco et al, 2018

7 : The Denver Post, 2019

8 : Hajek et al, 2019

9 : MChem et al, 2017

10 : Notley et al, 2018

11 : http://www.odoxa.fr/sondage/hausse-prix-tabac-cigarette-electronique-ont-impact-important-baisse-nombre-de-fumeurs/