The degree of effectiveness of electronic cigarettes depends on what effect is being measured. Research shows that the most commonly reported reason for using electronic cigarettes was “to help me stop smoking tobacco entirely”. Current smokers report that the main reason for using the device is to “help me reduce the amount I smoke but not stop completely”.
Effectiveness also varies between products and between users according to their experience in use.
Currently in the UK, any nicotine-containing product which claims or implies that it can treat nicotine addiction is considered to be a medicinal product and is therefore subject to regulation. Consequently, electronic cigarette manufacturers have avoided making such explicit claims.
Furthermore, the WHO has stated that “the electronic cigarette is not a proven nicotine replacement therapy. Nevertheless, survey data suggests that, whatever the reason electronic cigarette use may have been initiated, about 4 in 10 users in currently use them in an attempt to quit smoking.
Another benefit of electronic cigarettes is that electronic cigarette use leads to abstinence among some smokers who had not intended to quit.
Empirical data on the effectiveness of electronic cigarettes as nicotine delivery devices are still being collected. Some reports from the published literature suggest that electronic cigarettes are inefficient nicotine delivery devices and result in only modest and unreliable increases in plasma nicotine levels. Such findings appear to apply particularly to new users whereas studies using participants experienced in electronic cigarette use have been found to derive more reliable nicotine intake levels.
Nevertheless, growing evidence suggests that electronic cigarettes are becoming more reliable in their nicotine delivery and that they have a beneficial impact in reducing subjective cravings and, in turn, number of cigarettes smoked. Moreover, some studies have demonstrated an ability for certain brands of electronic cigarettes to reduce nicotine cravings despite delivering low plasma nicotine levels.
Another feature of electronic cigarettes is an ability to provide superficial aspects of the experience of smoking. This has been demonstrated by users exhibiting reduced cravings, withdrawal symptoms and number of cigarettes smoked per day even when given a placebo electronic cigarette.