New Clinical Trial Shows E-Cigs Help Smokers Quit and Reduce Cravings

By Lindsay Fox Posted December 10, 2014

Quitting Smoking with E-Cigs

E-cigarettes do help you quit smoking. Even if you aren’t satisfied with the multitude of anecdotal evidence available online, population-based and clinical studies confirm that vapers do successfully quit smoking quite often, despite widespread claims that “e-cigs haven’t been proven effective for quitting.” The most well-known randomized controlled trial compared e-cigs to patches, and found that the e-cig group quit smoking slightly more than the patches group, but this was an insignificant difference. The big problem with this finding is that first-generation cig-a-like models were used, which are widely expected to be less effective than newer eGo-style devices or mods and are now effectively obsolete. So what happens when you conduct a trial on second-generation e-cigs? As the researchers of a new study have found: e-cigs significantly reduce cravings and many smokers – even ones with no intention of quitting – successfully kick their combusted tobacco habit.




  • 48 smokers with no intention of quitting were randomized to either receive one of two eGo-style e-cigs (with differing capacities) or to smoke cigarettes (the control group).
  • The study was conducted in two parts: a lab study looking at effects on cravings at three meetings over two months and a six-month follow up period. The control group was given e-cigs at the last lab session to use during the six-month follow up.
  • 21 percent of all participants were abstinent from smoking at the end of the eight-month study, and overall there was a 60 percent reduction in the number of cigarettes smoked.
  • Quit-rates were highest after five months, at 37 percent of the e-cig group and 38 percent of the control group (who’d switched to vaping three months before).
  • During the first lab session, after smoking a cigarette or vaping for five minutes, both group showed similar reductions in cigarette cravings. By the second and third sessions, the e-cig groups’ cravings for cigarettes had decreased overall (even prior to vaping).
  • Overall, there were very few complaints about e-cigarettes and satisfaction was moderate to high. When the control group was smoking, there were more complaints about cigarettes than e-cigarettes.


The Study – How Well Do Second-Generation E-Cigs Work for Quitting Smoking?


The study (full text available for free) used a randomized controlled trial design, splitting 48 participants (all smokers of more than ten cigarettes per day with no intention of quitting) into three groups at random: two e-cigarette groups (using one of two eGo batteries, one 650 mAh and one 1000 mAh) and one control group who smoked their normal cigarettes at first before being given an e-cigarette after a couple of months.


The study can be split into two parts. Firstly, there were three sessions over the course of eight weeks conducted in a lab, designed to look at differences in cravings and withdrawal symptoms after vaping (or smoking) following four hours of abstinence. Between sessions, participants could vape or smoke as they wished, according to their assigned group. After the initial eight weeks, the second stage of the study involved participants using their e-cigs as desired, with follow-ups at three months and six months (five and eight months from the start of the study) to look at changes in their smoking and vaping behavior. Reported smoking status was verified objectively using exhaled carbon monoxide testing.


For the second part of the study, the control group – who’d smoked during the lab sessions – was given e-cigs and became the “switch group.” The core difference was that the switch group was simply given e-cigs with no further guidance, while the two e-cig groups were given instructions and guidance when they first received their devices. This was to assess whether there was a difference in outcome between vapers with no guidance on their use and those with guidance.


The Results – E-Cigs Curb Cravings and Reduce Smoking

eGo e-cigs reduce cravings

The lab results investigating smoking or vaping’s effect on cravings suggest that e-cigarettes are effective at reducing cigarette cravings. During the first session, five minutes of smoking or vaping led to a notable decrease in cigarette cravings (compared to the start of the session), and the degree of the decrease was the same for both groups. For the second two lab sessions, there was a decrease in cravings for both groups, but this was bigger in the cigarette-smoking group. This was likely because the e-cig user groups had significantly lower cravings for cigarettes to start with at the second and third sessions (even before vaping) compared to at the start of the first session, indicating that their cravings had been shifted onto e-cigs as opposed to tobacco cigs. The cigarette group showed no significant decrease in cravings between sessions.


By the third session, e-cig users’ cravings for tobacco cigarettes didn’t even increase from the end of the vaping period to the end of the (roughly hour-long) session, whereas for the cigarette group (and the vapers at earlier sessions) cravings increased the longer they went without nicotine. The e-cig users showed an increase in craving for e-cigs during the periods after vaping at all sessions.


As you would expect, the exhaled quantities of carbon monoxide in the vapers’ breath didn’t increase after vaping, whereas the smokers did show increases. In the latter two sessions, the baseline levels of exhaled carbon monoxide also decreased in the vapers but not in the smokers.


At the end of the two months of lab sessions, 34 percent of the e-cig groups had quit smoking entirely. Up to this point, the cigarette smokers were still all smoking. After the full eight months had elapsed (and the control group of smokers had been vaping for six months), 19 percent of the e-cig groups and 25 percent of the original control group (now the “switchers”) had quit smoking entirely, working out to 21 percent of the participants as a whole. The quit-rates for both groups were slightly higher at the first follow-up (after five months of vaping for the e-cig groups and three months for the switching group), with 37 percent of the e-cig group and 38 percent of the switching group being abstinent.


But completely quitting is only part of the story, since e-cigarettes often lead to substantial reductions in the number of cigarettes smoked per day. The researchers found that the number of cigarettes smoked by the e-cigarette group decreased dramatically after just one week of vaping, while the control group of smokers consumed the same amount. In each week of the lab study individually or averaged over the whole initial two months, the e-cig groups smoked substantially fewer cigarettes than the control group. When the group of smokers was given e-cigs, just like with the original e-cig groups, their cigarette intake decreased dramatically (by the same amount, too).

E-Cigarette quit smoking rates

For the e-cigarette group, there was a 77 percent reduction in the number of cigarettes smoked from their baseline assessment to the end of the lab study: going from just over 20 cigarettes per day to just less than five per day. For the whole group over the entire study period, 60 percent fewer cigarettes were smoked per day at the last follow-up compared to the start of the study. Throughout the study, the specific e-cig used didn’t make a difference on craving reduction, quitting or the decrease in cigarettes smoked.


Finally, the researchers looked at the reported complaints about e-cigarettes and their benefits. Overall, the vaping groups reported very few complaints, and there were generally more complaints about the cigarettes than the e-cigarettes. When the control group switched to vaping, the difference between the number of complaints disappeared, and both reported an increase in benefits from vaping from the first lab session to the first follow-up.


Through all of this, it’s worth noting that the number of participants was pretty small. While the results are still valuable evidence, more participants would have made it more likely that the group is representative of the population as a whole. There’s no reason to think that it isn’t, and a larger clinical trial on smokers not intending to quit (using less effective devices) had similarly positive results. The design may have limited the effectiveness of vaping too, because the participants were encouraged to only use a tobacco liquid, whereas evidence suggests that variety in flavors is important for quitting.




The authors conclude that second-generation e-cigarettes were immediately and highly effective in reducing cigarette cravings, and that vaping resulted in remarkable reductions in smoking or complete abstinence. Importantly, this didn’t differ whether or not participants were guided in the use of e-cigs, indicating that just giving smokers – even those who don’t want to quit – an e-cigarette will reduce their cigarette consumption and thereby reduce their risk of developing tobacco-related illnesses. In short, e-cigarettes work just as intended. For those determined to continue claiming that e-cigarettes are ineffective, there is now one more clinical study attesting to the fact that they’re talking complete nonsense.