March 15, 2023

In November of 2022, PRI published an article prepared by Dr. Cheryl K. Olson, MPH, Sc.D. entitled “Vaping as a Harm Reduction Solution to Tobacco Use – A Summary for Physicians.” Dr, Olson had previously served as a member of the Harvard Medical School Research facility for over 15 years. She is well known in the public health community and is a sought-after lecturer on matters of public health. Her article appears below.

One response to her article was to question whether that was her individual “opinion” or whether it was an opinion shared in the public health community. PRI then asked Dr. Olson to respond to this question. Her response appears directly below.

A fair summary of her response is the following: It may be that the electronic cigarette is the most disruptive and effective technology yet seen with respect to smoking but one that the public health community has, not only, failed to endorse but has, in most instances, actively opposed. Recently, however, certain members of the public health community have come to the realization that vaping is a most effective tool in ending cigarette smoking. Indeed, there is now “high certainty evidence” that vaping works better than nicotine replacement therapies to stop patients from smoking.

PRI believes that there is no reason for the perfect to be an enemy of the good and would recommend this material to its member Medical Societies and their physician members.

– Joseph (Jay) A. Schwartz III

President, Physicians Research Institute

With “High Certainty,” E-Cigarettes Can Ease Patients Off Cigarettes

By Cheryl K. Olson, MPH, Sc.D.


  • People who smoke are more likely to quit with vaping than with nicotine patches and gums.
  • This “high certainty evidence” comes from an independent Cochrane systematic review of 78 studies.
  • All studies found a clinically important benefit from using nicotine e-cigarettes.
  • Serious adverse events were rare, and similar for e-cigarettes and NRT.

There is now “high certainty evidence” that vaping works better than nicotine replacement therapies (NRT) to help patients who smoke. So says a recent update of the internationally respected Cochrane Collaboration’s systematic review, Electronic Cigarettes for Smoking Cessation[i].

“Our new review found the strongest evidence yet that e-cigarettes with nicotine help people to quit smoking better than traditional nicotine replacement therapies, such as patches and chewing gums,” says lead author Jamie Hartmann-Boyce.

The review’s dozen authors are affiliated with respected institutions such as the University of Oxford and Harvard Medical School. Quitting was defined as stopping smoking for at least six months.

The updated systematic review included 78 studies with over 22,000 people who smoked. Most studies were “gold standard” controlled trials and cross-over trials, with patients randomized to e-cigarettes or a control condition. The rest were uncontrolled intervention studies with everyone assigned to vape. Quit rates could potentially be higher among people who freely choose to try e-cigarettes.

Cochrane took the unusual step of making this a “living” systematic review, to revise as new evidence comes in about e-cigarette effects and safety. What’s coming in future updates?

“More evidence, particularly about the effect of newer e-cigarettes with better nicotine delivery than earlier ones, is needed to assist more people quit smoking,” says Hartmann-Boyce. “Longer-term data is also needed.”

We also know relatively little about effects of e-cigarette flavors and options. There’s preliminary evidence from Cochrane that people who vape to quit smoking find it helpful to switch between flavors.[ii]

Q&A: Cochrane Findings

Why vape to quit smoking? As the full Cochrane review’s introduction says, multiple factors support tobacco dependence. A cessation product that eases nicotine withdrawal symptoms and also mimics “the rituals and sensations that accompany smoking” might have an edge.

Exactly how well did vaping work? For every 100 patients randomly assigned to use e-cigarettes, 9 to 14 stopped smoking for at least six months. By comparison, six in 100 patients assigned to NRT quit smoking (as did 4 in 100 patients who used no quitting aids). For those who like the math: e-cigarette users were 1.6 times more likely to have quit than NRT users (RR 1.63; 99% CI 1.30 to 2.04).

Is it safe to vape to quit smoking? The most-mentioned unwanted effects were throat and mouth irritation, headache, cough, and feeling sick. These got better with time. Serious adverse events were rare among all groups in these studies, about two per 100. With moderate certainty, rates of problems were about the same for e-cigarette users and NRT users.

More information for busy physicians:

What does “high certainty evidence” mean? How Cochrane works

Headquartered in the U.K., Cochrane is an international nonprofit and independent network of researchers who carry out systematic reviews of evidence. The goal is to help doctors make everyday treatment decisions. Cochrane’s website states that they “do not accept commercial or conflicted funding.”

“Electronic Cigarettes for Smoking Cessation” is what’s called an intervention review, intended to assess effectiveness and/or safety of a treatment or procedure. Because it’s also a living review, researchers scan monthly for new studies that fit their criteria, and publish full updates as warranted.

Cochrane reviews come with an evidence quality grade: this study got the highest possible grade.


[i] Hartmann-Boyce J, Lindson N, Butler AR, McRobbie H, Bullen C, et al. Electronic cigarettes for smoking cessation. Cochrane Database of Systematic Reviews, 17 November 2022.

[ii] Lindson N, Butler AR, Liber A, Levy DT, Barnett P et al. An exploration of flavors in studies of e-cigarettes for smoking cessation: secondary analyses of a systematic review with meta-analyses. Addiction 2022; 1-12. DOI: 10.1111/add.16091

[iii] Warner KE, Benowitz NL, McNeill A, Rigotti NA. Nicotine e-cigarettes as a tool for smoking cessation. Nature Medicine Feb. 2023,

November 18, 2022

A State Medical Society member of PRI recently requested information on the value of vaping as a harm reduction solution to tobacco use. There is considerable information, pro and con, with respect to the subject of vaping and PRI was unable to give its member Medical Societies an informed answer. Accordingly, the PRI Board decided to retain an expert with respect to vaping and related issues.

Cheryl K. Olson, MPH, Sc.D., holds a doctorate from the Harvard School of Public Health and was a member of the Harvard Medical School Research faculty for over 15 years. She has an extensive publication record and is a sought-after lecturer on matters related to public health. The PRI Board decided that she would be an ideal person to report to PRI and its member State Medical Societies with respect to vaping and related issues.

Dr. Olson’s report was made possible by a Grant from the Foundation for a Smoke-Free World, Inc. (“FSFW”), a US nonprofit 501(c)(3), independent global organization.

The contents, selection, and presentation of facts, as well as any opinions expressed herein are those of Dr. Olson and under no circumstances shall be regarded as reflecting the positions of the Foundation for a Smoke-Free World, Inc.

–Joseph (Jay) A. Schwartz III
President, Physicians Research Institute

Vaping as a Harm Reduction Solution to Tobacco Use A Summary for Physicians

Cheryl K. Olson, MPH, Sc.D.

Key Points

  • Over 30 million adult Americans still smoke.
  • Cigarettes take nearly half a million lives each year.
  • Today’s smokers have more disadvantages; quitting is harder.
  • Standard cessation treatments (nicotine replacement therapies and medications) usually fail.
  • Most physicians misperceive the risks of nicotine; the danger arises from combustion.
  • Electronic nicotine delivery systems (e-cigarettes) are a legal alternative.
  • Smoking is at least 20 times more harmful than vaping nicotine.
  • In randomized controlled trials and population surveys, e-cigarettes outperform nicotine replacement therapies. Even smokers not planning to quit do so with vaping.
  • Switching from smoking to vaping leads to rapid measurable reductions in biomarkers of harm.

Who still smokes today?

More people than you think! You probably count few, if any, smokers among your colleagues. In 1965, when 42% of U.S. adults inhaled tobacco, college graduates were about as likely to indulge as the less-educated (Drope, 2018). That may give the impression that smoking is disappearing.

Wrong. According to the U.S. Centers for Disease Control and Prevention, over thirty million Americans still use cigarettes: twenty-five of every 200 adults. Smoking is less visible today because it’s increasingly concentrated in what public health researchers call “vulnerable populations.”

People who lack health insurance or use Medicaid are more than twice as likely as those with private insurance to smoke (Zhu, 2017). Today’s smokers are often unemployed or low income, less educated, and dealing with chronic mental or physical health issues, or heavy alcohol use. Studies find that the more disadvantages such as these a person faces, the more likely they are to smoke, and the more difficulty they have quitting (Leventhal, 2019). In other words, there are no easy wins left in today’s war on smoking.

The urgent need to move patients off cigarettes

As a U.K. evidence update shows (McNeill 2022), smoking remains “the largest single risk factor for death and years of life lived in ill-health globally.” Cigarettes continue to kill nearly half a million (480,000) of our fellow Americans every year.

A New England Journal of Medicine review (Carter, 2015) of smoking and mortality found that among current smokers, the rate of death from any cause was two to three times as high compared to people who never smoked. The authors noted that 17% of the excess mortality involved conditions not typically associated with smoking; for example, smokers face twice the death rate from renal failure. In short, we may be underestimating smoking’s toll.

Recent publications give new angles on familiar risks. One highlights the increased risk of cardiovascular disease across subtypes among people who smoke, along with average earlier onset and shorter survival times (Khan, 2021). Another notes that in just one year (2019), 2.2 million person-years of life were lost in the U.S. to smoking-related cancers (Islami, 2022), along with an estimated $21 billion in lost earnings.

The limits of cessation medicines

Today’s quit-smoking medications are failing most smokers. A recent analysis in Preventive Medicine highlighted the limits of nicotine replacement therapy (NRT) products, varenicline, and bupropion (Rosen, 2021). Study authors modeled best-case effectiveness, using randomized controlled trial estimates of efficacy—trials typically include behavioral counseling not available to most smokers. The results? Using current recommended methods, just 2.3% of smokers would quit, equaling a reduction in U.S. population-level smoking prevalence of 0.3%.

These result align with multiple population studies that have found no effect of NRT, bupropion or varenicline on one-year smoking abstinence rates. In other words, the available patches and pills barely budge the needle on real-world smoking levels. As study coauthor Vaughan Rees, of Harvard’s School of Public Health, said at the 2022 E-Cigarette Summit, “The best evidence-based interventions are dated, overrated and cannot meet the challenge of reducing tobacco-related harm in this century.”

What physicians get right and wrong about nicotine

The general public and physicians alike share misperceptions that nicotine by itself is dangerous to health. To quote a 2021 survey from the Journal of General Internal Medicine, “Nicotine is responsible for the highly addictive nature of tobacco products, but most tobacco-caused disease is not directly caused by nicotine, but rather by other chemicals present in tobacco or tobacco smoke” (Steinberg, 2020). Stunningly, four of five physicians in this U.S. survey strongly (and wrongly) agreed that nicotine causes cancer, cardiovascular disease, and chronic obstructive pulmonary disease (COPD). There were only minor variations across medical specialties.

A follow-up study testing variations in question wording found similar results (Manderski, 2021). This miscasting of nicotine as the primary health villain is concerning and dangerous. It may make doctors hesitate to recommend nicotine replacement therapies or reduced-risk nicotine products to smokers who seem unable to quit.

When quitting nicotine is not realistic: Harm reduction

Recognizing these facts, more tobacco control experts are focusing on reducing its harm, to as close to zero as possible. They view tobacco products as falling along a continuum of risk: cigarettes are extremely toxic; NRTs and non-combustible products cause far less harm; and no use results in no harm (Abrams 2018).

Abstinence from tobacco use is the ideal. The next-best result, for individuals who can’t or don’t want to quit nicotine, is movement down the continuum of risk: away from combusted tobacco to a less harmful product. As researchers Dorothy Hatsukami and Dana Carroll of the University of Minnesota note, “Most in the tobacco control community would agree that an immediate main goal is to rapidly eliminate tobacco-related death and disease” (Hatsukami, 2020).

One possible alternative: E-cigarettes

Given all this, could electronic nicotine delivery systems—e-cigarettes—be a more effective means to reduce morbidity and mortality among your patients who still smoke? A growing body of research says yes.

Most media coverage of e-cigarettes, and many research articles, focus on vaping’s potential to addict teens. Fifteen past presidents of the Society for Research on Nicotine and Tobacco, writing in the American Journal of Public Health, state, “We believe the potential lifesaving benefits of e-cigarettes for adult smokers deserve attention equal to the risks to youths” (Balfour, 2021).

As alternatives to the standard combustible cigarette, a wide variety of e-cigarette devices have been developed in the past two decades. They include disposable e-cigarettes, “closed system” devices using replaceable pods or cartridges, and “open system” devices which can be highly customizable and used with any e-liquid. Based on the most recent Behavioral Risk Factor Surveillance System data, 5.1% of U.S. adults were current (past-month) e-cigarette users in 2020, with 2.3% being daily users (Boakye, 2022).

Regulation of vaping

No e-cigarettes have been approved as smoking cessation devices by the U.S. Food and Drug Administration. However, the FDA has a Center for Tobacco Products tasked with reviewing novel nicotine products, based on that “continuum of risk” idea (Gottlieb & Zeller, 2017). Companies must submit an extensive array of studies, called Premarket Tobacco Product Applications (PMTA), to provide evidence that the marketing of their product meets the statutory standard of “appropriate for the protection of public health.”

In contrast to the “safe and effective” standard used to approve new medicines through the FDA’s Center for Drug Evaluation and Research, the APPH standard is meant to balance the risks and benefits of a new nicotine product to the population as a whole, including smokers, non-users, and youth (U.S. FDA, 2022). Some vaping products have received “marketing granted” orders; many other products remain legally on the market while under review.

Most doctors know little about vaping

If you’re puzzled about e-cigarettes, and their potential risks and benefits, you are far from alone. A review from the University of Queensland (Erku, 2020) found 45 qualitative and quantitative studies internationally on physician beliefs and behaviors regarding e-cigarettes. Doctors were aware of vaping, but far from expert in its health effects and use for smoking cessation. Most of what they knew came from popular media stories or advertising, the internet, or patient reports. The authors note, “This lack of knowledge and feeling of being ‘uninformed’ was reported consistently by [health care professionals] across and within studies.”

What we know (and misbelieve) about e-cigarette risks

“Vaping poses only a small fraction of the risk of smoking” says a comprehensive review by the U.K. Office for Health Improvement and Disparities (formerly known as Public Health England). To help the public and health professionals understand the magnitude of the difference in risk between vaping and smoking, these experts state: “Smoking is at least 20 times more harmful to users than vaping” (McNeill, 2022).

What about cancer, heart disease, and COPD? The U.K. report concludes:

  • “Vaping generally leads to lower exposure to many of the carcinogens responsible for the health risks of smoking.”
  • “Based on the toxicant profile in vaping products and aerosols” the risk of vaping to cardiovascular health “is expected to be much less than that of cigarette smoking.”
  • For smokers, “switching to vaping is likely to slow down the development of respiratory diseases.”

Authorities in the U.S. concur. In their 774-page consensus study report, Public Health Consequences of E-Cigarettes, the National Academies of Sciences, Engineering and Medicine (2018) conclude, “Laboratory tests of e-cigarette ingredients, in vitro toxicological tests, and short-term human studies suggest that e-cigarettes are likely to be far less harmful than combustible tobacco cigarettes.”

Some misconceptions about e-cigarettes have taken off in popular media based on minimal evidence. A handy list of myths and correctives can be found on the U.K. Health Security Agency website.

Vaping is not risk-free, and people who don’t use nicotine products should not start. As research findings continue to accumulate, we’ll have a better grasp on vaping’s relative risks and benefits for subgroups of patients.

Vaping for smoking cessation: What surveys show

Results from large ongoing population surveys show that vaping works in the real world to help people stop smoking—even smokers who didn’t plan to quit. A few examples:

  • The International Tobacco Control Four Country Smoking and Vaping Survey looked at real-world smoking quit attempts in the U.S., Australia, Canada and England. Vaping is now one of the most commonly used quitting aids, about equal to nicotine replacement therapies (Gravely, 2021).

    The authors’ advice? “Healthcare providers should be prepared to discuss the use of NVPs [nicotine vaping products]. Particularly if smokers are seeking advice about NVPs, wanting to try/or already using an NVP to quit smoking, have failed repeatedly to quit with other cessation methods, and/or if they do not want to give up tobacco/nicotine use completely.”

  • Many concerns about youth vaping have focused on flavors, but flavored products may improve quit rates for adult smokers. Population Assessment of Tobacco and Health (PATH) Study analyses show that for adults, uptake of vaping is associated with smoking cessation, and those who choose to vape a non-tobacco flavor do better (Friedman & Xu, 2020). Another PATH study analysis (Glasser, 2021) found that “consistent and frequent e-cigarette use over time” boosted smoking cessation.
  • Vaping can help even the toughest cases: daily smokers with no plans to quit and lower-than-average education levels and incomes. A PATH analysis (Kasza, 2021) found that when such smokers began vaping daily, 45.5% discontinued daily smoking, and 28% quit cigarettes altogether. That’s eightfold-greater odds of quitting with daily vaping.

Vaping for smoking cessation: What clinical trials and systematic reviews show

Clinical studies, including gold-standard randomized controlled trials (RCTs), find that vaping works better than gums and patches, in part because smokers prefer vaping and stick with it longer.

  • With “moderate certainty,” the respected Cochrane Collaboration finds quit rates are higher (RR 1.53) for smokers randomly assigned to e-cigarettes vs. to nicotine replacement therapies. Its latest systematic review of e-cigarettes for smoking cessation had 61 studies (16,759 smokers), including 34 RCTs (Hartmann-Boyce 2021). Vaping may also help with relapse prevention; an updated analysis found that 70% of subjects who’d stopped smoking using e-cigarettes were still vaping six months or more later (Butler, 2022).
  • What about smokers who’ve repeatedly failed to quit with the usual treatments? Vaping works six times as well. A U.K. RCT found that after six months, 19.1% of smokers randomized to vaping (choice of e-liquid flavors/strengths) had quit, versus just 3% of those who had their choice of six NRT options (patches, gums, inhalers, sprays, microtabs) (Myers Smith, 2021).
  • Along with helping smokers quit, e-cigarettes can rapidly reduce harm. A Cochrane secondary analysis found reductions in 12 of 13 biomarkers among vapers compared to smokers. The authors conclude, “Switching from smoking to vaping or dual use appears to reduce levels of biomarkers of potential harm significantly” (Hartmann-Boyce, 2022).
  • Looking at African-American and Latinx smokers: A U.S. RCT found that, among subjects randomized to use e-cigarettes (JUUL), 28% were vaping-only after six weeks, with another 58% dual-using and just 14% returning to smoking-only. The e-cigarette group had reduced carcinogen exposure (expired carbon monoxide; urinary NNAL concentration) and improved respiratory symptoms (Pulvers, 2020).
  • Pregnant people should be strongly encouraged to quit smoking; smoking during pregnancy is linked to a number of adverse outcomes. A new RCT found that e-cigarettes may help women who smoke while pregnant to quit, and did “not seem to pose larger risks than the use of NRT, despite the fact that ECs were more likely to be used and were used for longer periods than NRT” (Pesola, 2022).

Resources for talking about vaping

Just providing advice to smokers does little to help with quitting (Stead, 2013). And as shown above, cessation patches and pills have a poor track record. Weighing the risks and benefits, e-cigarettes are an option worth considering.

Surveys suggest that patients typically hear about e-cigarettes from the media, family or friends, and vape shops; few hear about them from physician offices. But most patients who had used e-cigarettes would like their primary care provider to talk with them about vaping (Doescher, 2018). Where do you start?

  • Physicians can save lives by correcting widespread patient misperceptions about relative risks. People who accurately view cigarettes as much more dangerous are more likely to try using vaping to quit smoking (Yong, 2022).
  • In a recent New York Times article (Miller, 2022), Jonathan Foulds of the Penn State University College of Medicine recommended two resources on vaping that your patients may find useful: 1) UK National Health Service information: and 2) the personal experiences of people who used vaping to quit smoking

  • Qualitative research offers more insights into the lives of patients who smoke, and how smokers quit with vaping (Notley, 2018).

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