It is becoming increasingly difficult to make the case against e-cigarettes on the basis of scientific evidence. A second Cochrane Review--the gold standard when it comes to assessing the state of the evidence on hot topics from salt to fat to smoking--has concluded that these nicotine-delivering devices that involve no combustion may help smokers quit without serious health consequences. The review concluded that of all 24 studies included, not a single one reported serious health risks to vapers from up to two years of e-cigarette use. Like the first review in 2014, this update is guarded, but also gives an approving nod to 15 currently ongoing randomized controlled trials that are underway.
But while the evidentiary needle has moved another tick in favor of e-cigarettes, this latest report is sure to add fuel to a raging firestorm. Remarkably, the ongoing battle is not one that pits public health against industry, as in the century-long struggle against Big Tobacco. Rather, e-cigarettes have ignited a bitter imbroglio within a community of scientists all bent on drastically reducing if not eliminating the prevalence of combustible cigarettes.
At stake are two key tensions. The first relates to how we weigh risk. What do we do in the absence of scientific certainty about all possible harms? These questions were at the heart of a furious exchange of letters between scientists over the course of 2014. This feud over e-cigarettes can't be understood absent the values that animate it.
Framing the position of tobacco control champions who favor e-cigarettes is Michael Russell. A psychiatrist and pioneer of smoking cessation methods, he famously wrote in 1976, "people smoke for nicotine but they die from the tar." Many physicians and public health practitioners have extended this perspective to e-cigarettes: e-cigarettes represent a disruptive tool that can drastically reduce if not eliminate the enormous burden of death and disease attributable to traditional cigarettes.
From this harm reduction perspective, risky behavior is inevitable. Going cold turkey when it comes to an addiction like smoking has its limits. Even if e-cigarettes carry some risks, those risks are far less serious than those of smoking. Thus, weighing the risks of e-cigarettes always involves a comparison to the well-documented harms of smoking.
On the other side of the debate are tobacco experts who have dedicated their careers to taking down the tobacco industry and are worried about the reglamorization of smoking. "We can't allow e-cigarettes to establish themselves the way cigarettes did and, five years from now when all the scientific questions are answered, try to stuff the genie back in the bottle," said Dr. Stanton Glantz, who advocates tighter regulation.
For those who hew to this precautionary perspective, until the uncertainty about e-cigarettes is definitely resolved, these devices have no place in a public health anti-tobacco arsenal. And there is uncertainty regarding the harms smokeless products may pose, particularly in the face of unknowns about how the FDA's new regulatory regime may impact quality control. But even if e-cigarettes may be a better option for any individual smoker who wants to quit and has tried other means but failed, how might they change the epidemiological pattern of disease in the long run? The most fundamental question, in other words, isn't how e-cigarettes might help or harm individuals, but whether they will change population-level smoking patterns in the long run.
This tension between harm reduction and precaution, then, highlights a second vital question involving the populations of concern. Whose risk matters?
In 2015, Public Health England, the United Kingdom's equivalent to the US Centers for Disease Control and Prevention (the CDC), roiled the waters when it endorsed e-cigarettes as a harm reduction tool. Remarkably, while they immediately drew fire from the editors of the Lancet and the British Medical Journal, they received the backing of ASH, the major NGO in the UK with an unimpeachable record of staunch opposition to tobacco. Public Health England was joined in 2016 by the Royal College of Physicians, which broadly advocated for a harm reduction approach to smoking that included not only e-cigarettes but also other forms of smokeless tobacco.
The positions of those British organizations that embraced e-cigarettes reflected a long history not just of support for harm reduction as a strategy. But the stance was also determined by a specific focus of concern. For the UK organizations, public health efforts should be directed to populations in immediate, certain danger: smokers themselves.
In the U.S., in sharp contrast, the major federal and voluntary agencies have remain staunchly opposed, not only because of the logic of better safe than sorry, but also because of a focus on a very different population: vulnerable youth and other non-smoking populations for whom e-cigarettes might provide a gateway to deadly cigarettes. Former FDA commissioner David Kessler and Campaign for Tobacco-Free Kids president Matthew Myers wrote in an op-ed in the New York Times last year, "we cannot afford to waste more time while the tobacco industry addicts another generation of kids." For those who advocate precaution, protecting populations that haven't yet been seduced by tobacco has remained of paramount importance even if the risks of a gateway effect are uncertain. For the non-smoker, an e-cigarette does nothing but increase risk.
Scientific data alone cannot tell us what to do. We cannot avoid interpreting the emerging evidence on e-cigarettes without reliance on values and priorities: harm reduction or precaution; immediate peril or hypothetical risks. So while there can be no question that the public health community must keep its fingers on the pulse of emerging scientific data regarding the risks and benefits of e-cigarettes, that is never enough. Let's acknowledge the debates about values that animate both the scientific and public controversy over e-cigarettes. Only then will we have a true picture of the science.