The Vaping Study You Haven’t Heard Of

A report from the Mayo Clinic looked at 70,000 patients and found no link between e-cigarettes and COVID-19.

Did you hear about the big new study on vaping and COVID-19? If you didn’t, that’s not surprising. The study didn’t find any association between the two—that is, it found no evidence suggesting that people who vape are more likely to be diagnosed with the disease. Research that leads to null results rarely gets much coverage in the media. In this instance, however, it upends the flood of stories throughout the pandemic that reported that vapers are at greater risk. The New York Times, for example, reported in September that “Vaping Links to COVID Risks Are Becoming Clear.” CNNWiredScientific AmericanUSA Today, and just about every other major news source you can name ran similar stories.

The new study is from a reputable source (the Mayo Clinic) and boasts a large sample of patients (nearly 70,000). Unlike much previous research on tobacco use and COVID, it also sorted patients by their current or former use of tobacco products, as well as the specific products they used (smoking, vaping, or both). In other words, the study had a near-ideal design for detecting whether and what kinds of nicotine consumption may lead to elevated risk of a SARS-CoV-2 infection.

In addition to finding no association between use of e-cigarettes and COVID diagnosis, the study reports that current smokers were found to be at lower risk of infection of COVID than nonsmokers. (Smoking still has plenty of downsides, including elevated risk of death from numerous causes.). Users of both cigarettes and e-cigarettes fell in between the two groups.

Those results are a complete departure from both the typical tone of reporting on the topic and, well, what anyone might have reasonably expected from a respiratory virus. And although the methodology is sound, it’s worth the caveat that one shouldn’t read too much into just one study. But it’s just the latest piece of evidence that vapers have been subjected to excessive fearmongering about COVID. Anomalous findings related to tobacco use and COVID have been apparent since early 2020—and the popular indictment of vaping in particular has been mostly speculative from the beginning.

Much of the anti-vaping coverage was itself driven by a single study from Stanford, published in the Journal of Adolescent Health, that found elevated likelihood of COVID diagnosis among adolescents and young adults who vape. The authors surveyed 4,351 people ages 13–24 and concluded that a “COVID-19 diagnosis was five times more likely among ever-users of e-cigarettes.” In a response published in the same journal, scientists criticized its relatively small, potentially unrepresentative sample and confusing results. (Having ever used an e-cigarette, for example, was significantly associated with higher risk—but having used e-cigarettes recently was not. That’s weird!) The Stanford study was fair game for reporting, especially during a pandemic when everyone was trying to learn as much about how to protect themselves as possible. But the accompanying alarm and calls for prohibition—such as by Democratic congressman Raja Krishnamoorthi, who claimed that “the youth vaping epidemic has combined forces with the Coronavirus pandemic, creating a much deadlier foe”—failed to reflect the tenuousness of its conclusion.

Importantly, urgent health advice based on a single study merits follow-up when more data comes in. A major new study finding no association between vaping and COVID infection certainly qualifies. If the Stanford study earned widespread headlines about the dangers of vaping, why has the Mayo Clinic study with its larger sample and better methodology received virtually no mention whatsoever?

Such one-sided reporting on vaping research is problematic for several reasons, not the least of which is the possibility of getting important stories wrong. It can also do harm by contributing to popular misperceptions that vaping is just as dangerous as smoking, as occurred with the misnamed “e-cigarette or vaping associated lung injuries” (“EVALI” or “vape lung”) outbreaks in 2019, undermining the goal of convincing smokers to switch to safer sources of nicotine. (The long decline in cigarette sales appeared to pause last year, likely due in part to bans on flavored e-cigarettes and negative press coverage of vaping.)

Raising alarm without appropriately solid justification also contributes to attitudes of mistrust toward media and health authorities. The internet has democratized access to scientific papers, so when news stories go beyond the evidence or ignore contradictory research, online communities will figure it out. In recent years, vaping enthusiasts have watched as anti-tobacco activists have warned of danger after danger, from “popcorn lung” to EVALI, demonizing e-cigarettes for causing massive harms that turned out to be highly exaggerated or actually attributable to other products. As a result, many now suspect that activists and legislators are using the pandemic as an opportunity to advocate for restrictive policies and lifestyle commandments that they favored as part of a preexisting agenda.

Accurate reporting on tobacco, nicotine, and COVID would tell a story that’s both more complicated and more interesting than the scary one that has dominated headlines. An ongoing evidence review of smoking and COVID now in its 11th iteration, and including more than 400 studies, is frustratingly ambiguous. Like the Mayo Clinic study, the review finds that for reasons that are still unclear (although there are theories), current smokers appear less likely to be infected with SARS-CoV-2. It’s unknown whether this is due to an actual causal effect or some other factor. At the very least it’s an intriguing result that curious science journalists might want to investigate—but it’s rarely mentioned in stories about tobacco use and the pandemic.

The review also examines whether smokers who do contract COVID suffer worse outcomes than nonsmokers. Interestingly, it’s true that former smokers consistently appear at higher risk of disease severity, hospitalization, and death, affirming fears that the accumulated damage smoking does to one’s body can affect its ability to fight a respiratory virus. Confusingly, however, outcomes for current smokers are “inconclusive,” with “no important associations with hospitalisation and mortality” but “a small but important association with disease severity.” It’s difficult to pull a coherent story about smoking from these results, and one should be more wary still of extrapolating from them to make declarations about vaping.

This is all fascinating, in the sense that it reveals that even seemingly obvious questions can prove difficult to answer in the midst of a pandemic wrought by a novel virus. Here goes a constant refrain of science: More research is needed. For all the ink spilled linking vaping to COVID, the topic just hasn’t been studied much, and even given the Mayo Clinic study, new research could change our understanding at any time. This tangle of evidence is a reminder that science is provisional and that in lieu of simple narratives, sometimes all we can confidently say is that “it’s complicated.”

As with many issues during the pandemic, coverage of its alleged link to vaping would have benefited from greater acknowledgment of uncertainty. Experts and journalists could have simply outlined the reasons to worry about heightened risks and emphasized sensible precautions, such as not sharing vaping devices, and then continued to follow the research. They should have also considered the possibility that anti-vaping alarmism may subvert the effort to transition smokers to safer sources of nicotine. We shouldn’t lose sight of that goal’s importance: While the threat of COVID in the United States is hopefully receding, smoking still causes more than 480,000 premature deaths each year, more than current CDC estimates of American pandemic deaths in 2020.

When I previously covered smoking, vaping, and COVID for Slate back in April of 2020, I predicted that future findings would be unlikely to provide much reason for changing how we evaluate tobacco harm reduction—that is, vaping may not be harmless, but it is a vastly healthier alternative to smoking. Nothing we’ve learned in the past year alters the expectation that countless lives would be saved by smokers quitting cigarettes, whether by complete abstinence or by switching to lower-risk alternatives. If the steady stream of news coverage demonizing vaping over the past year dissuades smokers from making that switch—especially if alleged links to COVID are not corroborated with better evidence—it may end up doing more harm than good to the cause of ending the much longer plague of deaths caused by smoking.