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Balancing Consideration of the Risks and Benefits of E-Cigarettes David J. K. Balfour, DSc, Neal L. Benowitz, MD, Suzanne M. Colby, PhD, Dorothy K. Hatsukami, PhD, Harry A. Lando, PhD, Scott J. Leischow, PhD, Caryn Lerman, PhD, Robin J. Mermelstein, PhD, Raymond Niaura, PhD, Kenneth A. Perkins, PhD, Ovide F. Pomerleau, PhD, Nancy A. Rigotti, MD, Gary E. Swan, PhD, Kenneth E. Warner, PhD, and Robert West, PhD

See also Samet and Barrington-Trimis, p. 1572.

The topic of e-cigarettes is controversial. Opponents focus on e-cigarettes’ risks for young people, while

supporters emphasize the potential for e-cigarettes to assist smokers in quitting smoking. Most US health

organizations, media coverage, and policymakers have focused primarily on risks to youths. Because of

theirmessaging,much of the public—includingmost smokers—nowconsider e-cigarette use as dangerous

as or more dangerous than smoking. By contrast, the National Academies of Science, Engineering, and

Medicine concluded that e-cigarette use is likely far less hazardous than smoking. Policies intended to

reduce adolescent vaping may also reduce adult smokers’ use of e-cigarettes in quit attempts.

Because evidence indicates that e-cigarette use can increase the odds of quitting smoking, many scientists,

including this essay’s authors, encourage the health community, media, and policymakers tomore carefully

weigh vaping’s potential to reduce adult smoking-attributable mortality.

We review the health risks of e-cigarette use, the likelihood that vaping increases smoking cessation,

concerns about youth vaping, and the need to balance valid concerns about risks to youths with the

potential benefits of increasing adult smoking cessation. (Am J Public Health. 2021;111(9):1661–1672.

https://doi.org/10.2105/AJPH.2021.306416)

The use of nicotine-containing elec-

tronic- or e-cigarettes has divided

the tobacco control community along a

spectrum from fervent opponents to

enthusiastic supporters. Opponents

emphasize that vaping can cause nico-

tine addiction among young people and

could lead some to become dependent

cigarette smokers, possibly

“renormalizing” smoking. They cite

research indicating that nicotine may

harm adolescents’ developing brains.

Some consider vaping’s health risks

substantial, and somequestionwhether

vaping decreases smoking cessation.1

By contrast, proponents present evi-

dence that vaping assists smokers in

quitting smoking and believe that vaping

poses far less risk to users’ health than

does smoking. Smoking among youths,

they observe, has declined rapidly dur-

ing vaping’s ascendancy.2

Many US governmental health agen-

cies3–6 and nongovernmental medical7,8

and health organizations9–12 focus pri-

marily onvaping’s risks for youngpeople.

These organizations’ pronouncements

and their influence on policymakers and

the media have had a profound impact

on the public’s understanding of vaping.

A study of US news articles on

e-cigarettes found that, from 2015 to

2018, 70%ofarticlesmentionedvaping’s

risks for youths, while only 37.3% noted

potential benefits for adult smokers.13

Of respondents to a 2019 national sur-

vey, nearly half considered vaping nico-

tine just as harmful as or more harmful

than cigarette smoking. Only 1 in 8 con-

sidered vaping less harmful. (The rest

responded “I don’t know.”14) By contrast,

the US National Academies of Sciences,

Engineering, and Medicine15 and the

BritishRoyalCollegeofPhysicians16have

concluded that vaping is likely far less

hazardous than smoking cigarettes.

The public’s inaccurate perception

worsened following a 2019 vaping-

associated acute pulmonary disease

outbreak (named “e-cigarette or vaping

use-associated lung injury” [EVALI]) that

caused 68 fatalities.17 Media coverage

was extensive. Several states and cities

promptly banned retail and online sale

of flavored e-cigarettes.18 In early 2020,

however, research attributed the illness

to vitamin E acetate, an adulterant in

illicit tetrahydrocannabinol (THC) vaping

devices shown to produce pulmonary

injury inanimals.19–21A small percentage

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of patients with EVALI reported vaping

only nicotine, but they were primarily in

states where THC was illegal, and most

had no toxicology testing.22 Once the

potential harm of vitamin E acetate was

publicized and adulterated THC

removed from themarket, the incidence

of new cases fell precipitously.19 Yet,

after the outbreak, two thirds of

respondents to a poll related the lung

disease deaths to use of “e-cigarettes

such as JUUL.” Only 28% related the

deaths to use of “marijuana or THC e-

cigarettes.”23

Scientists differ in their views of the

relative risks and benefits of vaping nic-

otine, and of their implications.1,2,24,25

Many, including this article’s authors,

believe that vaping can benefit public

health, given substantial evidence sup-

porting the potential of vaping to reduce

smoking’s toll. Our objective is to

encourage more balanced consider-

ation of vaping within public health and

in the media and policy circles.

In the following pages we address:

� the health risks of vaping,

� the likelihood that vaping increases

smoking cessation,

� the principal concerns about youth

vaping, and

� balancing concerns about risks to

youths with potential benefits for

adult smokers.

THE HEALTH RISKS OF VAPING

According to the National Academies of

Sciences, Engineering, and Medicine,

“Laboratory tests of e-cigarette ingre-

dients, in vitro toxicological tests, and

short-term human studies suggest that

e-cigarettes are likely to be far less

harmful than combustible tobacco ciga-

rettes.”15(p1) The British Royal College of

Physicians similarly concluded that

“vaping isn’t completely risk-free but is

far less harmful than smoking

tobacco.”16

High-quality clinical and epidemio-

logical data on vaping’s health effects

are relatively sparse. There are no data

on long-term health effects, reflecting

the relative novelty of vaping and the

rapid evolution of vaping products.

Determining even short-term health

effects in adults is difficult because

most adult vapers are former or cur-

rent smokers.

Some studies find that vaping may

worsen asthma, bronchitis, and cough,

including among nonsmoking young

people.26,27 By contrast, a few studies

found that smokers with asthma or

chronic obstructive lung disease see

symptoms improve after switching to e-

cigarettes.28,29 Randomized switching

trials (cigarettes to e-cigarettes) docu-

ment improvements in respiratory

symptoms.30,31

Laboratory studies have reported

potentially adverse effects of

e-cigarette aerosol in cells and ani-

mals.26,32 It is difficult, however, to

extrapolate from exposure conditions

in cells and animals to humans.26

Human experimental studies have

focused on acute effects,33 which may

not predict future disease. For example,

e-cigarettes acutely impair tests of

endothelial function, a common feature

of cardiovascular disease, but when

smokers switch from cigarettes to

e-cigarettes, endothelial function nor-

malizes.34,35 A recent study detected no

difference in biomarkers of inflamma-

tory and oxidative stress in exclusive

e-cigarette users and nonusers of

either cigarettes or e-cigarettes.36

There is little evidence that

e-cigarettes pose significant cancer

risk.15 However, some studies raise

concerns that warrant long-term follow-

up of vapers.37,38

Many scientists have concluded that

vaping is likely substantially less dan-

gerous than smoking because of the

following15,16:

� Thenumberof chemicals in cigarette

smoke, greater than 7000,39

exceeds that of e-cigarette aerosol

by 2 orders of magnitude.40,41

� Among potentially toxic substances

common to both products, ciga-

rette smoke generally contains sub-

stantially larger quantities than

e-cigarette aerosol.42–44 However,

e-cigarette aerosol contains some

substances not found in cigarette

smoke.45

� Biomarkers reflecting exposure to

toxic substances are present at

much higher levels in exclusive ciga-

rette smokers than in exclusive

vapers, and studies of smokers who

switch to e-cigarettes find decreases

in toxicant exposures.31,46–50

� Tests of lung and vascular function

indicate improvement in cigarette

smokers who switch to e-ciga-

rettes.28,29,34 Exclusive users of

e-cigarettes (most being former

smokers) report fewer respiratory

symptoms than do cigarette smok-

ers and dual users.51

However, questions remain.52 Ongo-

ing research will lend further insight into

the products’ absolute and relative

dangers.

THE LIKELIHOOD THAT VAPING INCREASES SMOKING CESSATION

A growing body of evidence indicates

that vaping can foster smoking cessa-

tion, although the evidence is not

definitive.53,54

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Randomized Trials

In an English smoking cessation ran-

domized controlled trial,55 smokers

assigned to e-cigarettes achieved nearly

twice the rate of biochemically con-

firmedsmoking cessationat1 year (18%)

than smokers assigned to nicotine

replacement therapy (9.9%); all received

identical behavioral counseling. While

80% of those who quit with e-cigarettes

were still vaping, they were no longer

exposed to smoking’s substantially

higher risk.

A New Zealand trial found that at 6

months, nicotine patch with nicotine

e-cigarettes outperformed patch with

nicotine-free e-cigarettes and patch

alone. Thus, in addition to aiding quitting

when used alone, nicotine e-cigarettes

may increase the effectiveness of exist-

ing cessation aids.56

Examining 26 randomized controlled

trials, a recent Cochrane Review con-

cluded that “There ismoderate-certainty

evidence that ECs [electronic cigarettes]

with nicotine increase quit rates com-

pared to ECs without nicotine and com-

pared to nicotine replacement

therapy.”53 Another meta-analysis drew

similar conclusions, albeit with less cer-

tainty.57 However, the US Preventive

Services Task Force’s smoking cessation

practice guideline did not find the evi-

dence convincing.58 As such, and for

reasons theCochrane Reviewdescribes,

more well-designed clinical trials are

needed.

Noteworthy is the lack of trials by

e-cigarette manufacturers in pursuit

of regulatory agency approval to use

e-cigarettes for smoking cessation,

likely reflecting the profitability of

selling e-cigarettes as consumer

products, rather than medicinal

devices.

Population Studies

Collectively, population studies’ findings

are consistent with a near doubling of

quit attempt success, found in the ran-

domized controlled trials, and the fact

that e-cigarettesare smokers’mostused

aid in quit attempts.59 Four studies60–63

found significant increases in smoking

cessation (10%–15%) that the authors

associated with vaping. A Centers for

Disease Control and Prevention study

reported that, in 2018, 15.1%of smokers

had quit smoking for 6months or longer

using e-cigarettes, compared with 3.3%

using other noncigarette tobacco prod-

ucts and 6.6% using no tobacco prod-

ucts.64 Another study identified a near

doubling of self-reported cessation

among users of e-cigarettes or vareni-

cline compared with smokers not using

these products.65 Consistent with these

population studies, simulation analyses

have generally found that vaping

increases smoking cessation, avoiding

large numbers of premature

deaths.66–69

Other researchers have found regular

and frequent e-cigarette use to be

associated with increased smoking ces-

sation, while infrequent usewasnot.70–75

This could reflect self-selection, with

frequent vapers possibly liking vaping

more and being more motivated to quit

smoking. Infrequent vapers might use

vaping as a temporary nicotine source

where smoking is prohibited.73,76

Other researchers have reported

reduced cessation rates among smok-

ers who vape.77,78 However, many failed

to distinguish frequency of vaping,

introducing the risk of the selection

biases just noted. Other studies

included only current vapers who also

smoke, systematically excluding vapers

who had successfully quit smoking.53,78

An often-cited meta-analysis found

vapers’ odds of quitting smoking 28%

lower than for nonvaping smokers.77

This analysis combined clinical trials,

cohort studies, and cross-sectional

analyses, an inappropriate practice for

meta-analyses.79 Furthermore, the indi-

vidual studies’ sources of bias could be

compounded in a meta-analysis, possi-

bly producing an incorrect result.76

Cigarette Sales

For years, US cigarette sales declined 2%

to 3% annually. More recently, as vaping

product sales increased, cigarette sales

decreased much more rapidly. Con-

versely, following the EVALI outbreak

and e-cigarette sales restrictions, sales

of e-cigarettes fell and sales of cigarettes

resumed their prevaping pattern.80

Studies finding a positive cross-price

elasticity of demand between cigarettes

and e-cigarettes support the conclusion

that the products are substitutes.81,82

Support for the plausibility of an

inverse causal relationship between

vaping and smoking comes from coun-

tries in which startling decreases in cig-

arette sales have accompanied rising

sales of another novel nicotine product,

heated tobacco products (HTPs). Like

e-cigarettes, HTPs exposeusers to lower

levels of toxicants than do cigarettes.83

In Japan, HTP adoption from 2015 to

2019 was accompanied by cigarette

sales declining by a third.84 In both

cases—HTPs in Japan ande-cigarettes in

the United States—as sales of reduced-

risk products rose, cigarette sales fell.

Unintended Consequences of Policies Restricting Vaping

Studies have found that policies

intended to restrict e-cigarette use may

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have unintentionally increased cigarette

smoking. One study associated a Min-

nesota e-cigarette tax with increased

adult smoking and reduced cessation,

estimating that taxing e-cigarettes at the

same rate as cigarettes nationwide

could deter 2.75 million smokers from

quitting smoking over a decade.85 Two

other studies found state restrictions on

minors’ access to e-cigarettes associ-

ated with higher adolescent cigarette

smoking.86,87

Implications

Although not the final word, the totality

of the evidence indicates that frequent

vaping increases adult smoking cessa-

tion. Smokers unable to quit smoking

with evidence-based cessation meth-

ods88 should bewell informed about the

relative risks of vaping and smoking and

vaping’s potential to help them quit

smoking. They should understand that,

while the long-term health consequen-

ces are unknown, completely substitut-

ing vaping for smoking likely reduces

health risks, possibly substantially.15

Dual use of cigarettes and e-cigarettes

will not have a comparable beneficial

effect.88 However, a period of dual use

may be necessary for some smokers to

transition from smoking. Because vap-

ing itself poses some risk, thebest advice

is to eventually stop vaping as well.

THE PRINCIPAL CONCERNS ABOUT YOUTH VAPING

Theprincipalobjections to vaping regard

3 potential effects on youths:

� Vaping can cause nicotine addiction

among young people who never

would have tried smoking.

� Vaping by never-smoking youths

may cause some to try smoking,

risking “renormalizing” smoking

among young people.

� Nicotine can harm developing

brains, and vaping nicotinemay have

other adverse health effects.

Vaping as a Cause of Nicotine Addiction

Vaping likely addicts some young people

to nicotine. However, the evidence does

not suggest it is addicting very large

numbers.89 Jarvis et al. concluded that

“Data . . . do not provide support for

claims of a new epidemic of nicotine

addiction stemming from use of

e-cigarettes.”90 Jackson et al. recently

reported that the e-cigarette–driven

increase in nicotine product use among

high-school students is not associated

with an increase in population-level

dependence.89 Among tobacco-naïve

youths, in addition to low vaping preva-

lence (9.1% in the past 30 days in 2020)

and frequency (2.3% vaping$20 days in

the past 30 days),91 small percentages

exhibited signs of nicotine

dependence.90

Frequent use is much more common

among current or former smoking

youths than among never-smokers.90

Many former smokers were already

addicted to nicotine before initiating

vaping. With high-school students’

smoking declining at an increasing

rate since youths began using

e-cigarettes,92,93 some may vape to

reduce or quit smoking.

Nonetheless, to the extent that vaping

creates nicotine addiction among oth-

erwise tobacco-naïve youths, concerted

efforts are needed to reduce youth

vaping. The new minimum age of 21

years for purchasing tobacco products

should help.94 Governmental agen-

cies3,95 and voluntary organizations12,96

disseminate vaping’s risks to youths

through Web sites, social media, and

television campaigns. Voluntary organi-

zations lobby Congress and state gov-

ernments to adopt policies restricting

youth access to e-cigarettes.

Recentpolicyattentionhas focusedon

restricting the availability of e-cigarettes

with flavors,97 a principal attraction for

youths.98–101While flavor bans could

reduce youth interest in e-cigarettes,

they could also reduce adult smokers’

vaping to quit smoking.102–104 Like

youths, adults prefer nontobacco fla-

vors,105 both groups favoring fruit and

sweet flavors.106,107

Policies regarding flavors reflect the

more general issue considered in this

article: the need to create a balance

between the sometimes-conflicting

goals of preventing youth vaping and

supporting adults’ smoking cessation

attempts, particularly for smokers

unable or unwilling to quit otherwise.108

Vaping Causing Smoking Initiation

Prospective studies have found that

young people who had vaped but never

smoked cigarettes were more likely to

have tried cigarettes severalmonths to2

years later than contemporaries who

had neither smoked nor vaped.15,109–113

Some commentators thus consider

vaping a “gateway” into smoking.114,115

Other observers believe the relation-

ship reflects a “common liability”116:

young people who vape are generally

more prone to risky behavior117; hence,

they might be more likely to try smoking

evenwithout vaping.118–121Three recent

studieshave concluded that vaping likely

diverts more young people from smok-

ing than encourages them to

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smoke.122–124 Conversely, some pro-

spective studies have found the

vaping–smoking relationship strongest

in youths at low risk of smoking.125–127

Obvious plausible correlates are often

not considered, however.128 Impor-

tantly, few studies include youths’ use of

other psychoactive substances, includ-

ing marijuana and alcohol. In 1 study,

inclusion of marijuana and 3 other vari-

ables eliminated the otherwise statisti-

cally significant link between vaping and

subsequent smoking.126,127Most stud-

ies do not even consider previous use of

tobacco products other than cigarettes.

Adjustment for confounders substan-

tially reduces the relationship between

vaping and subsequently trying

cigarettes.129

Numbers of cigarettes smoked at

follow-up are frequently very low, only 1

or 2 in the past 12 months in one

study.130 Furthermore, the prospective

studies generally have not examined

progression to regular dependent

smoking, with 1 recent exception.131

Only a small proportion of youths who

experiment with smoking become reg-

ular smokers. Kim and Selya found that

while e-cigarette use was associated

with ever trying smoking, it was not

associated with current continued

smoking.119 Pierce et al. recently con-

cluded the opposite.131 Shahab et al.

reported that less than 1% of US stu-

dents who initiated nicotine or tobacco

use with e-cigarettes were established

cigarette smokers.132

If vaping causes someyoungpeople to

try cigarettes, the aggregate impact

must be small. A recent study68 esti-

mated that if vaping increases non-

smoking youths’oddsof tryingcigarettes

by 3.5 (as reported by Soneji et al.109),

smoking initiation among young adults

would increase less than 1 percentage

point. Furthermore, US survey data

demonstrate that smoking among

young people has declined at its fastest

rate ever during vaping’s ascen-

dancy.92,93,133 If vaping increases smok-

ing initiation, other unknown factors

more than compensate.

Nicotine Harming Developing Brains

Animal model studies have found that

nicotine can affect maturation of brain

parts associated with executive function

and decision-making, potentially leading

to more impulsive behavior, cognitive

deficits, and greater likelihood to self-

administer other drugs.134,135 In addi-

tion, there is evidence in humans of

neurological changes attributed to nic-

otine in the brains of adolescent smok-

ers, interpreted by some as reflecting

similar harmful effects to those in the

animal models.136,137

These studies lead some researchers

to suspect that adolescent nicotine use

in any form may lead to long-term

structural and functional brain changes

with associated negative implications for

cognition or impulse control.138 How-

ever, given species differences and

questions about the relevance of

experimental animal nicotine dosing

paradigms to human use patterns, the

validity of extrapolation to humans is

speculative. Whether impaired brain

development with behavioral conse-

quences occurs in young nicotine con-

sumers is difficult to determine because

of potential confounding of genetic and

socioeconomic factors, the influence of

other substance abuse, and the role of

preexisting neuropsychiatric problems

associated with youth smoking.

Research has yet to isolate nicotine use

in the adolescent years and then exam-

ine later sequelae. Still, concerns about

brain function effects of nicotine

exposure through vaping deserve seri-

ous examination.98

Concerns About Youth Vaping in Context

Several considerations raise the ques-

tion of whether, for youth as a whole,

vaping creates dangerous levels of nic-

otine exposure that would not have

occurred in the absence of vaping.

� The large majority of nontobacco

product–using young people do not

vape and, thus, have no nicotine

exposure.90

� Among those who vape, most do so

infrequently; many are short-term

experimenters.90

� Frequent vaping is most common

among current or former smokers,

individuals already exposed to

nicotine.91

� The most dangerous form of youth

exposure to nicotine, cigarette

smoking, has declined at an

unprecedented rate during the era

of youth vaping.92,93,133 Use of other

tobacco products has declined as

well.139

Still, concerns emanating from sub-

stantial increases in youth vaping in

2018 and 2019 are readily understand-

able and important to address. A sizable

decline in 2020 is encouraging.139 We

must continuemonitoring youth vaping,

learning more about potential harms

and identifying effective prevention

strategies. However, as public health

groups, the media, policymakers, and

the general public focus on youth vap-

ing, vaping’s potential to help adults quit

smoking too often gets lost. That may

come at a significant public health cost.

Fourteen percent of US adults smoke;

smoking annually causes nearly half a

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million deaths. Anything that can reduce

that toll deserves serious attention.

With the focus on youths creating an

environment in which smokers believe

that vaping is as dangerous as or more

dangerous than smoking,14 many

smokers struggling to quit may be

unwilling to try vaping as an alternative.

This likely translates into less smoking

cessation than if smokers correctly

understood the relative risks of vaping

and smoking.

BALANCING CONCERNS ABOUT RISKS AND POTENTIAL BENEFITS

Research comparing vaping’s risks for

youths with potential benefits for adult

smokers has found the latter to

dominate,66 potentially avoiding the

smoking-produced loss of tens of mil-

lions of life-years.67,68 Vaping cannot

end cigarette smoking. But vaping can

complement tried-and-true methods of

reducing smoking, including taxes on

combustible tobacco products, smoke-

free workplace laws, marketing restric-

tions, plain packaging with graphic

warning labels, antismoking media

campaigns, tobacco-21 laws,94 and

evidence-based smoking cessation

treatment.88

We believe the potential lifesaving

benefits of e-cigarettes for adult smok-

ers deserve attention equal to the risks

to youths.140 Millions of middle-aged

and older smokers are at high risk of

near-future disease and death. Quitting

reduces risk.88 Young people will not

experience smoking-related (and con-

ceivably vaping-related) chronic dis-

eases for 3 decades, and likely not at all

if they quit within a decade or 2. Social

pressures to quit smoking will probably

remain strong, and quitting aids may

improve. Furthermore, as noted

previously, the rate of smoking among

young people has declined while vaping

has increased.92,93,133 Vaping may

addict some youths to nicotine, but

many fewer than popularly

believed.89,90

Seeking a Sensible Mix of Policies

To date, the singular focus of US poli-

cies on decreasing youth vaping may

well have reduced vaping’s potential

contribution to reducing adult smok-

ing. Those policies include taxing

e-cigarettes at rates comparable to

cigarette taxes,141 decreasing adult

access to flavored e-cigarettes thatmay

facilitate smoking cessation,103 and

convincing the public—including

smokers—that vaping is as dangerous

as smoking.14

The public health objective should be

to develop policies and interventions

that both reduce youth vaping and

increase adult smoking cessa-

tion.97,120,140,142 While an in-depth dis-

cussion of an optimal policy mix

exceeds the scope of this article, we

here present illustrative policies that

would serve this objective. These are all

in addition to conventional evidence-

based prevention and cessation

measures.

� Tax cigarettes and other combusti-

ble tobacco products heavily;

impose a more modest tax on

e-cigarettes. Taxes should be pro-

portionate to risk. A much higher

tax on combustibles will encourage

adult smokers to quit smoking or to

switch to less expensive

e-cigarettes. By raising the price of

e-cigarettes, a modest tax will dis-

courage their use by price-sensitive

youths.141

� Because both youth and adult smok-

ers find e-cigarette flavors

attractive,98–107 banning all (or most)

flavors risks reducing smokers’ use

of e-cigarettes to quit smoking102–104

at the same time that it reduces

youth vaping.99,101 An alternative

would be to limit the retail sale of

flavored e-cigarettes to adult-only

outlets such as vape shops. An

imperfect policy for either goal, this

approach could benefit both.

� Government agencies and health

organizations should develop

nuanced, targeted communications

that emphasize the realistic con-

cerns about youth vaping and, sep-

arately, the potential benefits of

e-cigarettes as less-risky (but not

risk-free) alternatives for adult

smokers otherwise unable or

unwilling to quit smoking.

� The US Food and Drug Administra-

tion (FDA) should strictly regulate

e-cigarette advertising and market-

ing, prohibiting all marketing

directed at, or attractive to, youths

and young adults, including all

“lifestyle” advertising. They should

limit advertising to a “switch” theme

directed clearly, and exclusively, to

adult smokers otherwise unable to

quit smoking.

� FDA should implement its thought-

ful comprehensive 2017 plan,143

mandating reduction of nicotine in

cigarettes to levels incapable of

sustaining addiction, while ensuring

the availability of consumer-

acceptable reduced-risk nicotine

products. To achieve the latter, the

agency should develop product

standards for products like

e-cigarettes, ensuring minimization

of risk associated with the product

class while maintaining consumer

acceptability.

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The Role of Nicotine in Tobacco-Produced Disease

FDA predicated its comprehensive

plan on recognition of the continuum

of risk in nicotine products.143 Nico-

tine is the chemical in tobacco that

fosters addiction. However, toxic

constituents other than nicotine, pre-

dominantly in smoked tobacco, pro-

duce the disease resulting from

chronic tobacco use.143,144 Nicotine-

yielding products vary in risk from

FDA-approved nicotine replacement

therapy products at the lowest end of

the risk continuum to combustible

cigarettes at the highest.

Unfortunately, the public has a dis-

torted view of the dangers associated

with nicotine per se. In a recent survey,

57% of respondents incorrectly

agreed that “nicotine in cigarettes is

the substance that causes most of the

cancer caused by smoking.” Only

18.9% disagreed. (The rest answered

“Don’t know.”)14 In a recent survey of

physicians, 80% strongly, but incor-

rectly, agreed that nicotine causes

cancer, cardiovascular disease, and

chronic obstructive pulmonary

disease.145

CONCLUSIONS

We share the very legitimate concerns

about youth vaping with the entire field

of public health. Our goal is to put those

concerns in perspective. We agree with

former SurgeonGeneral C. Everett Koop

who, in 1998, urged that “[A]s we take

every action to save our children from

the ravages of tobacco, we should dem-

onstrate that our commitment to those

who are already addicted . . . will never

expire.”146 The latter appears at risk

today.

While evidence suggests that vaping is

currently increasing smoking cessation,

the impact could be much larger if the

public health community paid serious

attention to vaping’s potential to help

adult smokers, smokers received accu-

rate information about the relative risks

of vapingandsmoking, andpolicieswere

designed with the potential effects on

smokers in mind. That is not happening.

The need to pay attention to adult

smokers is particularly important from a

social justice perspective. African Amer-

icans suffer disproportionately from

smoking-related deaths, a disparity that,

a new clinical trial shows, vaping could

reduce.31 Today’s smokers come dis-

proportionately from lower education

and income groups, the LGBTQ (lesbian,

gay, bisexual, transgender, and queer or

questioning) community,147 and popu-

lations suffering frommental health

conditions148 and from other drug

addictions.149 Smoking accounts for a

significant proportion of the large life

expectancy difference between affluent

and poorer Americans.150,151 For smok-

ers with serious psychological distress,

two thirds of their 15-year loss of life

expectancy comparedwith nonsmokers

without serious psychological distress

may be attributable to their smoking.152

Vaping might assist more of these

smokers to quit.148,153

To the more privileged members of

society, today’s smokers may be nearly

invisible. Indeed, many affluent, edu-

cated US persons may believe the

problem of smoking has been largely

“solved.” They do not smoke. Their

friends and colleagues do not smoke.

There is no smoking in their workplaces,

nor in the restaurants and bars they

frequent. Yet 1 of every 7 US adults

remains a smoker today.

Smoking will claim the lives of 480000

ofour fellowcitizens this year alone.

ABOUT THE AUTHORS David J. K. Balfour is professor emeritus with the Division of Systems Medicine, School of Medicine, University of Dundee, Dundee, UK. Neal L. Beno- witz is with the Department of Medicine, School of Medicine, University of California San Francisco. Suzanne M. Colby is with the Department of Psy- chiatry and Human Behavior, Alpert Medical School, Brown University, Providence, RI. Dorothy K. Hatsukami is with the Department of Psychiatry and Behavioral Sciences, Medical School, Univer- sity of Minnesota, Minneapolis. Harry A. Lando is with the Division of Epidemiology and Community Health, School of Public Health, University of Min- nesota. Scott J. Leischow is with the College of Health Solutions, Arizona State University, Phoenix. Caryn Lerman is with the Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles. Robin J. Mer- melstein is with the Department of Psychology, University of Illinois–Chicago. Raymond Niaura is with the Department of Epidemiology, School of Global Public Health, New York University, New York, NY. Kenneth A. Perkins is with the Depart- ment of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA. Ovide F. Pomerleau is professor emeritus with the Department of Psy- chiatry, Medical School, University of Michigan, Ann Arbor. Nancy A. Rigotti is with the Department of Medicine, Massachusetts General Hospital, Har- vard Medical School, Boston. Gary E. Swan is with the Stanford Prevention Research Center, Depart- ment of Medicine, Stanford University School of Medicine, Palo Alto, CA. Kenneth E. Warner is with the Department of Health Management and Policy, School of Public Health, University of Michigan. Robert West is with the Department of Behavioural Science and Health, University College London, London, UK.

CORRESPONDENCE Correspondence should be sent to Kenneth E. Warner, PhD, Department of Health Management and Policy, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109-2029 (e-mail: kwarner@umich.edu). Reprints can be ordered at http://www.ajph.org by clicking the “Reprints” link.

PUBLICATION INFORMATION Full Citation: Balfour DJK, Benowitz NL, Colby SM, et al. Balancing consideration of the risks and benefits of e-cigarettes. Am J Public Health. 2021; 111(9):1661–1672.

Acceptance Date: May 15, 2021.

DOI: https://doi.org/10.2105/AJPH.2021.306416

CONTRIBUTORS K. E. Warner wrote much of the original draft of the article and supervised revisions. N. L. Benowitz, S.M. Colby, D. K. Hatsukami, R. Niaura, N. A. Rigotti, and R. West drafted specific sections of the article or played lead roles in reviewing and revising article drafts. All authors reviewed all drafts critically, contributed significantly to revisions, and approved the final version of the article.

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ACKNOWLEDGMENTS The paper was presented by K. E. Warner at the E-Cigarette Summit: Science, Regulation & Public Health, USA Virtual Summit, May 25, 2021.

The authors are former presidents of the Society for Research on Nicotine and Tobacco (SRNT), the world’s leading professional organiza- tion dedicated to the subject. They are listed in alphabetical order. All 26 of the then–past presi- dents were invited to participate as co-authors of this article. (A 27th past president was the active president at the time of preparation of the article.) We were unable to reach one of them. Three were not included because of institutional commitments that they felt might be interpreted as conflicts of interest. The remaining 7 declined to co-author. Note. The opinions expressed in this article are

solely those of the authors. They do not represent those of SRNT, which has taken no organizational position on the issues discussed in this article and had no involvement in the preparation of this article.

CONFLICTS OF INTEREST N. L. Benowitz is a consultant to Pfizer and Achieve Life Sciences, companies that market or are developing smoking cessation medications, and has been an expert witness in litigation against tobacco companies. S. J. Leischow is conducting a clinical trial supported by Achieve Life Sciences, which is developing a nonnicotine medication for smoking cessation, and has consulted with them. He also consulted more than 1 year ago for GSK, which is working to bring a new nicotine- replacement product to market, and he receives medication for a National Institutes of Health– funded smoking-cessation study from Pfizer. N. A. Rigotti receives royalties from UpToDate Inc for writing about smoking cessation and e-cigarettes and is a consultant for Achieve Life Sciences for an investigational smoking-cessation medication. R. West has undertaken research and consultancy for Pfizer and GSK, companies that manufacture smoking-cessation medications.

HUMAN PARTICIPANT PROTECTION There were no human participants involved.

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