保健医療科学

2023

Vol.72 No.1 p.52－61

Topics: Recent topics in public health in Japan 2023

＜ Review ＞
Preventing tobacco use among young adults has significant implications
for public health in the future
TANO Rumi 1), HIRANO Tomoyasu 2)
1)
2)

Department of Health Promotion, National Institute of Public HealthInstitute for Cancer Control, National Cancer Center

Abstract
Even though the age of adulthood was lowered in Japan in April 2022, the minimal age of legal access(MLA) for tobacco products is maintained at 20 years, because the earlier the age of smoking initiation, themore likely one is at risk for tobacco-related diseases such as cancer and cardiovascular disease and thehigher the risk of premature death and individuals with younger age of smoking initiation are consideredmore likely to have difficulty quitting cigarettes. The smoking prevalence among junior and senior highschool students has significantly decreased, whereas that among those in their 20s are high, and the downward trend of smoking prevalence is slow. In contrast to the dramatic drop of smoking prevalence of juniorand senior high school students, the downward trend is not significant.
Smokers have been reported to have a combination of lifestyle disorders, such as an unbalanced diet andlack of physical activity, compared with nonsmokers. Given that the smoking behavior and attitudes of family members, friends, and others around smokers may be related to the smoking behavior of young people,
it seems important to avoid smoking and showing cigarettes around children as a countermeasure againstsocial factors.
In Japan, the minimum age of adulthood and the MLA have been separated by this revision of the Civil
Code. Considering the adverse health effects, raising the age from 20 years old to higher age should beconsidered a public health policy option. Comprehensive tobacco prevention and control programs should
reduce the number of smokers and incidence of tobacco-related diseases and deaths.
keywords: smoking initiation, young adults, tobacco products, raising the minimum age of legal access(accepted for publication, December 21, 2022)

I. Introduction
In April 2022, the age of adulthood was lowered in Japan.
For approximately 140 years, from the Meiji Era to today,
the age of majority in Japan was set by the Civil Code at 20
years of age [1]. This Civil Code was amended, and the ageof majority changed from 20 to 18 years on April 1, 2022 [1].
Recently, the voting age for the referendum on the revision of the Constitution and the voting age for the Public
Offices Election Law have been set at 18 years, and policies
have been promoted to treat 18- and 19-year-old persons asadults regarding decisions on important matters in national
politics. On the basis of this policy, it has been argued that
it is appropriate to treat persons 18 years of age or older asadults in the Civil Code, the basic law concerning civil life.
Worldwide, it has become common to set the age of majority at 18 years, and lowering the age of majority to 18 years
is considered respecting the right of self-determination ofyoung people aged 18 and 19 years and encouraging theiractive participation in society.
Conversely, even if the age of majority under the Civil
Code is lowered to 18 years, the minimal age of legal accessCorresponding author: TANO Rumi
2-3-6 Minami, Wako, Saitama 351-0197, Japan.
E-mail: tano.r.aa@niph.go.jp

52

J. Natl. Inst. Public Health, 72 (1) : 2023

Preventing tobacco use among young adults has significant implications for public health in the future(MLA) for tobacco and alcohol products is maintained at
20 years [2]. The age limit for public sports (horse, bicycle, auto, and motorboat racing) was also maintained at 20
years. These age limits are to be maintained as they werein the past because of concerns about health hazards andmeasures against gambling addiction [2, 3].
This paper aims to summarize the health hazards related to smoking among those less than 20 years of age, thecurrent state of public awareness regarding smoking, andissues related to smoking among young people and to provide reference and information for the formulation of healthpromotion plans and public health policy studies.

II. Smoking Initiation Age and Health Effects
There are reports indicating that developing cells are
susceptible and adversely affected by carcinogens or develop atherosclerotic lesions, and a causal relationshipbetween smoking and symptoms of cough, phlegm, shortness of breath, and decreased respiratory function has been
confirmed in underage smokers [4]. Additionally, domestic
and international studies have shown that the earlier theage of initiation of smoking, the more likely one is at risk oftobacco-related diseases, such as cancer and cardiovasculardisease, and the higher the risk of premature death (Figure1) [5, 6].
It has already been shown that the risk of cancer, especially lung cancer, varies greatly with the number ofcigarettes smoked per day as well as the smoking years.
Therefore, because the risk of lung cancer at a given age
increases with the number of cigarettes smoked during

Cancer2.11
1.71 1.65

1.5
1.0

1.0

An analysis of the intensity of nicotine dependence byage of habitual smoking initiation reports that the younger
the age that one starts smoking, the more dependent one
becomes. Those who started smoking in their teens are
more dependent on nicotine than those who started smoking in their 20s, and those who started in their 20s are more
dependent than those who started smoking in their 30s(Figure 3, left) [8]. A higher percentage of people are highly
dependent on nicotine: among those who began smoking intheir 30s or older, less than 30% have a dependence scoreof 9 or higher, whereas among those who began smoking
in their teens, more than 50% have a score of 9 or higher

0.5
0.0

2.0

2.32

0.3

2.22
1.61

1.5
1.0

1.0
0.5
0.0

Age at initiation of cigaretteAge at initiation of cigarettesmokingsmoking

Figure 1 Cancer and heart disease death rates by age at initiation of cigarette smoking [5, 6]

Annual Death Rate (%)

2.0

III. Age of Smoking Initiation and Intensityof Nicotine Dependence

Heart disease
2.5

Mortality ratio at age 40-79

Mortality ratio at age 40-69

2.5

one’s lifetime, i.e., the number of cigarettes smoked per day
and the number of years the person has smoked the risk is
expected to increase for those who started smoking early intheir lives.
As shown in Figure 2, the risk of dying from lung cancer
between the ages of 55 and 64 years is higher for those
who smoke 21 to 30 cigarettes per day than for those who
smoke 10 to 21 cigarettes per day, and in both cases, theearlier the age at which smoking starts, the higher the risk.
In all cases, the health risk increases the earlier the age ofinitiation of smoking [7].
It has been reported that the risk of lung cancer deaths
is approximately twice as high when smoking is initiated atless than 15 years of age than when it is initiated between
20 and 24 years of age [7].

0.2

0.1

0

Before 15

15‐19
10‐20/day

20‐24

25 or over

Never

21‐39/dayFigure 2 Relationship between age at starting regular cigarette smoking and lung cancer
death rates at 55–64 years in US men [7]J. Natl. Inst. Public Health, 72 (1) : 2023

53

TANO Rumi, HIRANO Tomoyasu

Figure 3 Nicotine dependence of current smokers by age of habitual smoking initiation(Figure 3, right) [8]. Those who began smoking at a younger age are considered more likely to have more difficulty
quitting cigarettes.
The figure on the right shows the percentage of people
who have a dependency ratio of n points or more. The pinkline represents the dependence level of those who initiatedsmoking in their teens, the yellow line represents those
who initiated smoking in their 20s, and the blue line represents those who initiated smoking in their 30s or older [8].

IV. Smoking Prevalence on a Downward Trend
The smoking prevalence for men continues to decline but
is still 27.1% in 2019, according to the most recent National
Health and Nutrition Survey [9]. The smoking prevalence
for women has leveled off to a slight downward trend, hovering at approximately 10%, and was 7.6% in 2019 (Figure4) [9]. The combined smoking prevalence for men andwomen has been declining over the last 50 years but has
recently shown a downward trend.
The definition of current smokers is the combination of

(%)
50
40
30

38.2
32.2 32.4
23.4

20
10
0

10.9

34.1

32.1 32.2

30.1 30.2 29.4 29.0

19.5 20.1 20.7 19.3 19.6 18.2 18.3

8.4

9.7

9.0

8.2

8.5

7.9

8.2

27.1

17.7 17.8 16.7

7.2

8.1

7.6

2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
all

men

women

Figure 4 Annual trend in the smoking prevalence of
current smokers (over 20 years old)54

daily and occasional smokers. Prior to 2011, the definition
was different [9].
The National Health Promotion Campaign, Healthy Japan 21 (second phase), set a target to reduce the smoking
prevalence from 19.5% in 2013 (the base year) to 12% by2022. However, in 2019, the most recent year of the survey,
the smoking prevalence was 16.7%, a decrease of only 2.8%
from the base year, making it difficult to achieve the numerical target at this rate [10].
The draft of the final report also states, “Since nohigh-impact measures have been implemented to reduce
the smoking prevalence, the smoking prevalence has
decreased by only 2.8% from the baseline, and it will bedifficult to achieve the target of 12% at this rate. Further
measures based on the Framework Convention on Tobacco
Control will be required in the future.” The report is rated
as “very good” [10].
Recently, heated tobacco products (HTPs) such as IQOS,
glo, and ploomTECH have become common. HTPs are usedby more than 20% of smokers. The use of HTPs is particularly high among young smokers, reaching approximately
40% among men and 50% among women in their 20s and
30s [9].
The appearance and spread of HTPs may be one of thereasons why smoking prevalence has been rapidly trending
downward, and the appearance and rapid spread of HTPs
represent a new threat to tobacco control.
Under the second phase of Health Japan 21, the goal isto eliminate smoking among minors (0%) by 2022 by promoting efforts to improve lifestyle and social environment
through a 10-year National Health Promotion Campaign.
In contrast, the Draft Final Evaluation Report of HealthJapan 21 (second stage) states that “B: Target has not beenreached, but is improving” and in part “B*: Improvement isbeing made, but the achievement of the target by FY2022 isin jeopardy” [10]. The final evaluation report (draft) statesthat “B: Target has not been reached but is improving” andin some cases “B* improving, but achievement of target
by FY2022 is doubtful.” In 2021, the smoking prevalence

J. Natl. Inst. Public Health, 72 (1) : 2023

Preventing tobacco use among young adults has significant implications for public health in the future

Figure 5 Recent trends of percentage of respondents who have smoked among junior and senior high school students
（％）
60
50
40
30

25.5

20
7.6

10
0

2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
men

women

Figure 6 Annual trends in smoking prevalence among young people in their 20s [9]among junior and senior high school students was 0.1% forfirst-year junior high school boys (Figure 5, top left), 0.1%
for first-year junior high school girls (Figure 5, top right),
1.0% for third-year high school boys (Figure 5, bottom left),and 0.6% for third-year high school girls (Figure 5, bottom
right) [10]. The smoking prevalence among junior and senior high school students in 2010, when the target was set,was 1.6% for first-year junior high school boys, 0.9% for

J. Natl. Inst. Public Health, 72 (1) : 2023

55

TANO Rumi, HIRANO Tomoyasu
first-year junior high school girls, 8.6% for third-year highschool boys, and 3.8% for third-year high school girls, a significant decrease [10].
Conversely, smoking prevalence among those in their
20s is high, and its downward trend is slow: in 2019, thesmoking prevalence among men and women in their 20s
was 25.5% and 7.6%, respectively (Figure 6), a rate similar
to the overall adult smoking prevalence rate (Figure 4) [9].
In contrast to the dramatic drop for middle and high school
students, the downward trend for 20s is not significant.
It will be necessary to explore smoking behavior and its
influential factors during this period, when smoking prevalence is low among middle and high school students but
jumps among those their 20s, and to consider countermeasures.

V. Tobacco Sales Volume
Cigarette sales volumes have been on a downward trend
since peaking in 1996, falling from 343.8 billion cigarettes
per year in 1996 to less than half, 155.7 billion cigarettes, inthe most recent year, 2019. In 2019, cigarettes accounted
for 24% of tobacco products (sum of cigarettes and HTPs)(Figure 7) [11]. The downward trend in the sales volume of
tobacco products, which includes both cigarettes and HTPs,
has not changed significantly and is thus far considered ashift among tobacco products.
Excerpted from the report of the Council on Fiscal Institutions, Ministry of Finance, Japan [11]. Sales of HTPs
began in 2012, but data were not taken prior to 2017.

3,500
3,000

3,483
3,107
75

777

2,700

2,500
950

2,000
1,500

3,032

728

2,706

1,000

1,680

1,708
253

667

561

1,749

500
0

1,833

1985

1996
(Imported)
Cigarettes

2006

1,653
354
496

1,557
376
460

1,104

1,014

894

804

720

2015

2016

2017

2018

2019

(Domestic)
Cigarettes

HTPs

Figure 7 Trend of annual sales volume of cigarettes and
HTPs

56

VI. Smoking Behavior among Young Adults
Smoking behavior among young people, including minors,
is shaped by the interaction of personal and social factors.
Not only personal factors such as knowledge, attitudes,
confidence in one’s own abilities, communication skills, andability to manage stress possessed by the individual but alsosocial factors such as the smoking status of family, friends,
and others around them; the status of smoking restrictions;and the availability of cigarettes are relevant. To prevent
smoking among young people, it is necessary not only to
spread knowledge about the health hazards of smoking
through antismoking education but also to create a social
environment that makes a tobacco-free society the norm [4].
The sale of cigarettes to persons under 20 years of age
is prohibited, and measures such as age verification at thetime of sale are mandatory. Vending machines have introduced “taspo,” an integrated circuit (IC) card for adultidentification, and convenience stores have introduced age
verification buttons [4]. In elementary, junior high, andhigh school education, guidance on the prevention of smoking, drinking, and drug abuse has been provided throughhealth and physical education, moral education, integrated
studies, and special activities [12]. The number of juvenile
delinquents caught smoking has also been greatly reduced.
In 2020, the number of juvenile delinquents arrested forsmoking was less than one-third of the number in 2011 [13].
Thus, measures for minors are steadily and surely having
an effect. In the future, efforts targeting young adults fromhigh school graduation to those in their 20s are required.
To live life in good health, it is important to have a goodlifestyle starting in your 20s. Smokers are susceptible not
only to various diseases but also to other lifestyle problems.
They are more likely than nonsmokers to have lifestyleproblems such as poor diet and lack of physical activity.
They have been reported to have a combination of lifestyledisorders, such as poor diet and physical inactivity, compared with nonsmokers [14]. Specifically, compared with
nonsmokers, they are 2.5 times more likely to miss breakfast, 1.3 times more likely to be inactive, 2.3 times more
likely to drink 40g alcohol or more, and 2.2 times more likely to intake highly salt [14].
Knowledge about the age of smoking initiation is notcommon. In a questionnaire that asked respondents toselect what they knew about the effects of a low age ofsmoking initiation, even the most common response, “A
low starting age for smoking increases the number of years
smoked,” was selected by 44.9% of respondents, less thanhalf of the total (Figure 8) [15]. This was followed by 42.9%
for “A lower age of smoking initiation increases the riskof disease,” 40.7% for “A lower age of smoking initiation

J. Natl. Inst. Public Health, 72 (1) : 2023

Preventing tobacco use among young adults has significant implications for public health in the future
increases nicotine dependence,” 36.3% for “A lower ageof smoking initiation increases the number of cigarettes
smoked in later life,” and 29.5% for “A lower age of smoking initiation increases the risk of early life” [15].
Another 29.9% responded “I don’t know anything in particular,” indicating that there is no significant widespreadawareness among the public about the health risks associated with a younger age of smoking initiation. It is an important issue to spread awareness of the relationship between
age of smoking initiation and health effects, especiallyamong younger people [15].
When compared by smoking status, there were no majordifferences in perceptions for many items, but differenceswere seen in risk perceptions of disease and early life. Particularly, compared with 44.1% of nonsmokers, 35.8% ofsmokers perceived that “a younger age at which smoking
starts increases the risk of disease.” Also, smokers’ perception of risk was higher than that of nonsmokers, with
24.2% of smokers and 27.4% of nonsmokers saying that “ayounger age at which smoking starts increases the risk ofpremature deaths” [15].
It has been reported that the largest factor influencing

intention to smoke as an adult or prediction of one’s futuresmoking behavior is the prediction of smoking behavior
at age 20 years, followed by adult male attitudes towardsmoking, gender, number of smokers in the family, andknowledge of the acute effects of smoking. The question ofwhether or not a person “wanted/thought of smoking cigarettes” at age 20 years, when smoking is legally allowed, isassociated with subsequent smoking behavior.
In the 2022 survey, when those currently aged 20 years
or older were asked whether they wanted to smoke cigarettes when they turned 20 years old, 27.3% of the respondents answered, “When I turned 20, I wanted to smoke
cigarettes” and 59.7% responded that they “did not want totry smoking cigarettes when I turned 20” (Figure 9) [15].
Investigating whether respondents wanted to smoke
cigarettes when they turned 20 years old, most smokers(61.3%) said they wanted to smoke cigarettes when theyturned 20 years old, whereas 14.3% said they did not wantto smoke cigarettes when they turned 20 years old (Figure9) [15]. Most of the nonsmokers did not want to smoke
cigarettes at the age of 20 years. Conversely, among nonsmokers, only 20.5% said they “wanted to smoke cigarettes

Percentage of respondents who know about age ofsmoking initiation and each health effect
0

10

20

(％)

30

40

44.9
46.3
44.6

Lower age of smoking initiation results in more
years of smoking

36.3
36.4
36.3

Smoking more cigarettes during later life at alower age of smoking initiation

40.7
39.4
41.0

Lower age of smoking initiation increases
nicotine dependence

Lower age of smoking initiation increases risk

35.8

of disease

Lower age of smoking initiation increases risk

24.2

of premature death

OthersDon't know any of theseAll[Current status] Smoker

50

42.9
44.1

29.5
30.5

0.3
0.1
0.3
29.9
30.4
29.8
[Current status] Non-smoker

Figure 8 Knowledge about adverse health effects and the age ofsmoking initiation [15]J. Natl. Inst. Public Health, 72 (1) : 2023

57

TANO Rumi, HIRANO Tomoyasu
0%All over 20 years old

20%

60%

27.3

80%

17.9

14.3

61.3

100%
9.8 2.11.1

59.7

Smokers over 20 years old

Non-smokers over 20 years old

40%

8.2 1.6 0.9

68.8

20.5

4.3 2.2

When I turned 20, I wanted to smoke cigarettes
When I turned 20, I did not want to smoke cigarettes
I don't know
I don't want to answer
Other

Figure 9 Responses to survey results on whether they wanted to smoke
cigarettes when they turned 20 years old [15]Reason respondents wanted to smoke cigarettes
when they turned 20 years old (M.A.)
0

10

20

30

（％）
40

60
51.7
51.5
52.2

Because my family smoked cigarettes and I wasfamiliar with cigarettes

35.5
34.3
39.0

Because a friend or acquaintance recommended
smoking to me

Because I saw advertisements and became
interested in cigarettes

9.3

13.7
15.2

10.3
11.4

Because I wanted to communicate in a smoking
room/area

6.8

20.2
18.4
25.4

Because I thought smoking scenes in TV dramas
and movies were cool

6.5
7.2
4.4

Because I thought smoking scenes in comics
were cool

Because I saw cigarettes in convenience stores

and/or vending machines and became interested
in cigarette

Because I became interested in cigarettes afterbrowsing information on the Internet

0.5

5.4
7.0

2.9
3.9

0.0

23.5
21.5

Because I saw someone smoking and wanted toimitate themof 20

Others[Current status] Smoker

29.3

13.1
13.4
12.2

Because I wanted to exercise my right at the age

All

50

1.8
1.6
2.4
[Current status] Non-smoker

Figure 10 Responses to survey questions regarding the reason for wanting
to smoke cigarettes (respondents who wanted to smoke cigarettes when
they turned 20 years old)58

J. Natl. Inst. Public Health, 72 (1) : 2023

Preventing tobacco use among young adults has significant implications for public health in the futurewhen I turned 20,” and the majority, 68.8%, said they “didnot want to smoke cigarettes when I turned 20” [15]. Thissuggests that there is a causal relationship between the intention to smoke at age 20 years and future smoking behavior. It is important to prevent people from thinking “I wantto smoke cigarettes when I turn 20 years old,” and therefore, antismoking education for minors and improvement of
the social environment are required.
The most common reason given for wanting to smoke
when they turned 20 years old was “Because my family
smoked and cigarettes were around me,” followed by “Because a friend or acquaintance recommended it,” “Because
I saw someone smoking and wanted to imitate them,” and“Because I saw an actor smoking in a TV drama or movie
and wanted to imitate him or her.” Conversely, the mostcommon answer was “because I was familiar with cigarettes.” However, the percentages of “because I want toexercise the rights that come with turning 20” and “because
I was interested in cigarettes after seeing cigarette advertisements” were not so high [15].
Nonsmokers were more likely to answer, “because I saw
actors smoking in TV dramas and movies and thought it
was cool” and “because I saw people smoking and wanted
to imitate them,” whereas nonsmokers were more likely toanswer, “because I saw cigarette advertisements and wasinterested in cigarettes” and “because I saw cigarettes on
display at convenience stores and vending machines andwas interested in cigarettes.” However, smokers tended
to be more likely to respond, “because I was interested incigarettes when I saw cigarettes on display or in vending
machines at convenience stores” and “because I was interested in cigarettes when I saw information on the Internet”(Figure 10) [15].
Given that the smoking behavior and attitudes of family
members, friends, and others around them may be related
to the smoking behavior of young people, it seems important to avoid smoking and showing cigarettes around children as a countermeasure against social factors.

tries have raised the minimum legal smoking age from 18
to 21 years [16, 17]. In New Zealand, a bill is being proposed to raise this age continuously so that children will nolonger be able to smoke as adults [18]. A committee in the
US FDA concluded that raising the nationwide MLA for tobacco products would likely immediately improve the healthof adolescents and young adults by reducing the number of
those with adverse physiological effects such as increased
inflammation and impaired immune functioning caused bysmoking, as these effects could potentially lead to negative
health consequences, including increased hospitalizations
and lessened capacity to heal wounds. Adverse maternal,
fetal, and infant outcomes – including preterm births, lowbirth weight, and sudden infant death – would also probably
decrease because of reduced tobacco exposure in mothers
and infants [19]. Raising the MLA will also lessen the population’s exposure to secondhand smoke and its associatedhealth effects, both at present and in the future. According
to the Institute of Medicine projects of the Centers for Disease Control and Prevention, US Department of Health &Human Services, if the age of sale was raise at present to
21 years nationwide, then “there would be approximately
223,000 fewer premature deaths, 50,000 fewer deaths fromlung cancer, and 4.2 million fewer years of life lost for thoseborn between 2000 and 2019” [19].
In Japan, the minimum age of adulthood and MLA havebeen separated by this revision of the Civil Code [1-3].
Considering the health effects, raising the age to 20 years
should be considered a public health policy option. As
shown in the description of Figure 3, it is believed thatthose initiating smoking in their 30s and older would beless dependent on nicotine and were more likely to quit
smoking early. Tobacco prevention and control activities
are a public health “best buy.” Evidence-based, nationwide
tobacco control programs that are comprehensive, sustainable, and accountable have been shown to reduce the number of smokers and incidence of tobacco-related diseases
and deaths [19].

VII. Future Issues and Countermeasures

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J. Natl. Inst. Public Health, 72 (1) : 2023

Preventing tobacco use among young adults has significant implications for public health in the future＜総説＞
若年層のたばこ使用の防止による公衆衛生の意義
田野ルミ 1），平野公康 2）
1）

国立保健医療科学院生涯健康研究部
国立がん研究センターがん対策研究所がん情報提供部

2）

抄録
日本では2022年 4 月に成人年齢が引き下げられたにもかかわらず，法的にたばこ製品が購入可能で喫煙できる最低年齢（MLA; Minimum age of Legal Access）は，20歳で維持された．これは，喫煙開始
年齢が早いほど，がんや循環器疾患などのたばこ関連疾患のリスクが高く，早世リスクが高いこと，および喫煙開始年齢が若い人ほどたばこをやめにくくなることが理由の一つとされている．厚生労働
科学研究費補助金の研究班による調査によると中高生の喫煙率は大幅に減少しているが，国民健康栄養調査などによる20代の喫煙率は依然として高い．中高生の喫煙率が劇的に低下しているのとは対照的に，その低下傾向は顕著ではない．
喫煙者は非喫煙者に比べて，偏った食事や運動不足などの生活習慣の乱れを併せ持つことが報告されている．また，若年喫煙者の周囲の家族，友人などの喫煙行動が，若年成人世代の喫煙開始に関係していると見られることを考えると，社会的要因への環境改善対策として，子どもの周囲で喫煙する
機会，子どもが身近にたばこを目にする機会をなくしていくことが重要となる．
今回の民法改正で成人年齢（18歳）とMLA（20歳）が分離され，18歳で成人しても法的に喫煙できない年齢層が生じることとなった．たばこの健康への悪影響の大きさを考えたとき，喫煙は20歳のままで良いのか．現在のMLAを20歳から引き上げる必要があるのかを考える必要があるのではないか．
外国では，MLAを引き上げる事例も報告されている．わが国においても，MLAの引き上げは公衆衛
生政策の選択肢として考えるべきではないか．MLA引き上げを含めた包括的なたばこ予防・管理プ
ログラムにより，喫煙者数，たばこ関連疾患および死亡の発生が減少することは明らかである．
キーワード：喫煙開始，若年層，たばこ製品，喫煙可能最低年齢の引き下げ

J. Natl. Inst. Public Health, 72 (1) : 2023

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