Juul-funded study (not surprisingly) finds that flavored Juuls help adults quit smoking

Christopher Russell and colleagues recently published “Factors associated with past 30-date abstinence from cigarette smoking in adult established smokers who used a JUUL vaporizer for 6 months” in the Harm Reduction Journal.  Their primary conclusion was “More frequent use of a JUUL vaporizer and primary use of JUUL pods in characterizing flavors, particularly mint and mango, appeared to be important to smokers' chances of quitting.”  They added that, “The impact of suspending retail sales of flavored JUUL pods on adult smokers' likelihood of quitting should be closely assessed.” 

In other words, cities, states and even the FDA should keep mint and mango pods – which are popular with kids – on the market to help adults quit smoking.

The paper is based on a large sample of 15,456 adult established smokers, which sounds pretty impressive until you look at how the sample was generated.  It came from 37,536 people who bought Juul online from Juul directly or responded to one of 500,000 flyers included in Juul packs inviting people to participate.   Judged against this universe of 514,456 possible respondents, the investigators only had a 2.9% response rate, well below what is considered reliable in survey research.

Even more important, such self-selected samples of consumer products are notorious for response bias  and selection bias, with people who are enthusiastic about the product much more likely to respond.

One way to try and deal with this problem is to compare people who responded to the survey with the larger population of Juul users based on a national random sample.  Despite having tons of statistics in the paper, the investigators didn’t both to do that.

Interestingly, the authors do note that the health benefits of switching would depend on the relative risks of Juul to conventional cigarettes (on page 17):

However, if the health risks of using a JUUL vaporizer are found to be similar to those associated with smoking cigarettes, the observed rates of complete switching and dual use of cigarettes and JUUL products would likely represent increased harm to the health of these adult smokers. Currently, there is insufficient evidence to conclude that switching completely from cigarettes to JUUL products may modify an adult smoker’s risk of developing serious health problems relative to continuing to smoke tobacco.   

The authors don’t bother to cite any of the studies showing substantial cardiovascular and pulmonary risks associated with e-cigarette use.  There is little attention to dual use either.

The Centre for Substance Abuse Research, where the study was done, has lots of ties to tobacco companies, including Fontem Ventures, Nicoventures, and Philip Morris International as well as Juul.

Policymakers should not rely on this study when assessing the effects of flavors on quitting.

The full citation is Russell C, Haseen F, McKeganey N.  Factors associated with past 30-day abstinence from cigarette smoking in adult established smokers who used a JUUL vaporizer for 6 months.  Harm Reduct J. 2019 Nov 7;16(1):59. doi: 10.1186/s12954-019-0331-5  and it is available here.