April 25, 2012
This is the first in a Series of four
papers about adolescent health
Centre for Adolescent Health,
Australia (Prof S M Sawyer MD,
G C Patton MD); Department of
Paediatrics, University of
Melbourne, Parkville, VIC,
Australia (Prof S M Sawyer,
G C Patton); Murdoch Childrens
Research Institute, Parkville,
VIC, Australia (Prof S M Sawyer,
Adolescent Health 1
Adolescence: a foundation for future health
Susan M Sawyer, Rima A Afifi, Linda H Bearinger, Sarah-Jayne Blakemore, Bruce Dick, Alex C Ezeh, George C Patton
Adolescence is a life phase in which the opportunities for health are great and future patterns of adult health are
established. Health in adolescence is the result of interactions between prenatal and early childhood development and
the specific biological and social-role changes that accompany puberty, shaped by social determinants and risk and
protective factors that affect the uptake of health-related behaviours. The shape of adolescence is rapidly changing—
the age of onset of puberty is decreasing and the age at which mature social roles are achieved is rising. New
understandings of the diverse and dynamic effects on adolescent health include insights into the effects of puberty
and brain development, together with social media. A focus on adolescence is central to the success of many public
health agendas, including the Millennium Development Goals aiming to reduce child and maternal mortality and
HIV/AIDS, and the more recent emphases on mental health, injuries, and non-communicable diseases. Greater
attention to adolescence is needed within each of these public health domains if global health targets are to be met.
Strategies that place the adolescent years centre stage—rather than focusing only on specific health agendas—provide
important opportunities to improve health, both in adolescence and later in life.
The present generation of people aged 10–24 years is the
largest in history—with a population of 1·8 billion,1 they
comprise a quarter of the world’s population. Nearly 90%
live in low-income and middle-income countries where
they constitute a far greater proportion of the population
than in high-income countries because of higher fertility
rates (figure 1). The growth in adolescent populations
coincides with a reduction in infectious disease, mal-
nutrition, and mortality in infancy and early childhood,
shifting attention to sexual and reproductive health,
substance misuse, mental health, injury, obesity, and
chronic physical illness, which become prominent during
adolescence and need very different responses.3,4
Many countries have entered a demographic transition
in which falling fertility and longer, healthier life
expectancy increase the proportion of people able to work.
A healthy, educated workforce has the potential to shape
a country’s economic prospects.5 Conversely, poverty,
inadequate education, mass unemployment, migration,
natural disasters, and war result in social environments
that can devastate the health of young people.6–11
Young people were at the forefront of the social unrest
across north Africa and the Middle East that began
in Tunisia in December, 2010. Although many succeeded
in toppling the restrictive regimes that they fought
against, they faced serious threats to their lives and
health. Such engagement is a powerful reminder that, by
stark contrast with younger children, adolescents have an
increasing capacity to be active agents of change within
their communities.11,12 It raises concerns about the extent
of young people’s exposure to violence, exploitation, and
abuse, and suggests the need for greater protection of
Many of the economic, educational, and political issues
that affect young people are interlinked. Invest ment in
education of adolescents has clear benefits to individuals
and their health, but is also a strategy for enhancing
employment, human rights, social capital, and
community wealth.5 The adverse effects of child marriage
and pregnancy at a young age (<18 years) on the health
and human rights of girls is well appreciated, but just as
potent is the dislocating effect of early pregnancy on girls’
education, skill development, and social networks, which
past 50 years.
their countries’ economic and social prospects.
mental disorder, and substance misuse). These determinants often cluster within
G C Patton); Department of
Health Promotion and
Community Health, Faculty of
Health Sciences, American
University of Beirut, Beirut,
Lebanon (Prof R A Afifi PhD);
Center for Adolescent Nursing,
School of Nursing
Department of Pediatrics,
of Minnesota, Minneapolis,
MN, USA; Institute of Cognitive
College London, London, UK
Department of Population,
Family and Reproductive
Health, Johns Hopkins
Bloomberg School of Public
Health, Baltimore, MD, USA
(B?Dick?MB); African Population
and Health Research Centre,
Nairobi, Kenya (A C Ezeh PhD);
and Consortium for Advanced
Research Training in Africa,
University of the
South Africa (A C Ezeh)
Prof Susan M Sawyer, Centre for
Adolescent Health, Royal
VIC 3052, Australia
all undermine their present and future health and
wellbeing, the health of their children, and their nations’
social and economic prospects.14,15
Societies typically define adolescence in terms of
age and social roles with little consistency between
countries. We focus on adolescents and young adults
aged 10–24 years (referred to as young people and youth
and hereafter referred to as adolescents) because this
age-group encompasses most individuals who are going
through the biological changes and social-role transitions
that historically defined adolescence (panel). Although
the biological sequences of puberty are highly consistent
(table 1), changes in the timing of puberty, the nature of
social-role changes, and the hopes and aspirations of
adolescents across the world are widely affected by
economic and sociocultural factors.
We assess the role of adolescence as a foundation for
future health, emphasising the changing context of
health and social development from late childhood to
early adulthood and the place of adolescents within global
public health. Our report is arranged around a conceptual
framework that we have developed to describe the many
factors affecting adolescent health and to put into context
the subsequent reports in this Series (figure 2).
Adolescence within the life course
Social disadvantage and negative experiences in infancy
and early childhood interfere with the achievement of
normal developmental milestones in later childhood, such
as healthy peer relationships and literacy.21 This can lead to
peer rejection, school disengage ment, academic failure,
and early uptake of risky behaviours in adolescence.21–23
Adoption of a life-course perspective promotes the
understanding that factors affecting preconception and
early childhood can cumulatively affect adolescents. Thus,
programmes intended to enhance maternal, infant, and
child health will also positively affect the health of
adolescents.24 However, although aspects of adolescent
health are known to be related to earlier determinants, less
emphasis has been placed on how adolescent health is
also the product of the biological and social experiences
that are specific to this phase of life (figure 2).
Similarly, policy makers have responded inadequately
to the knowledge that health-related behaviours (ie,
behaviours that positively or negatively affect health) and
health outcomes in adolescence have a sustained effect
on the future health of these young people. The life-
course approach promotes a different temporal under-
standing of prevention because many opportunities for
prevention of non-communicable diseases, mental
disorders, and injuries in adults arise from a focus on
risk processes that begin in or before adolescence.3,5,15,25
Many health-related behaviours that usually start in
adolescence (tobacco and alcohol use, obesity, and
physical inactivity) contribute to the epidemic of non-
communicable diseases in adults26,27—eg, in people older
than 60 years, high blood pressure and elevated
cholesterol and glucose account for 29% of disability-
adjusted life-years (DALYs); tobacco use accounts for
10%; physical inactivity for 7%; and being overweight or
obese for 7%.17
The health of pregnant adolescents in particular
contributes to the health of the next generation by affecting
developing fetuses. Viral infections such as rubella and
HIV, maternal malnutrition and micro nutrient deficiency,28
obesity and gestational diabetes,29–31 and health-related
behaviours such as the consumption of alcohol, tobacco,
and psychotropic drugs will affect the health of offspring.32,33
Impaired fetal growth is more common in pregnancy in
girls younger than 18 years and is a potent precursor of
adult diabetes.34 Specific transgenerational effects will be
particularly severe in countries where, in terms of nutrition
for example, both adolescent mal nutrition and micro-
nutrient deficiency are high and teenage pregnancy is
common. For example, in India, about half of girls aged
15–19 years are underweight and anaemic, and a similar
Figure 1: Distribution of people aged 10–24 years as a proportion of the population by country
proportion are married before age 19 years.14 Other
countries, such as South Africa, are grappling with the
double burden of both underweight and overweight
adolescents.35 Although it has not yet been described,
health-related behaviours of boys probably also have an
effect on the health outcomes of the next generation.
Puberty and social-role transitions
The onset of puberty has long been accepted as the starting
point of adolescence, and key social-role tran sitions such
as completion of education, employment, marriage, and
childrearing historically signalled the end. Until the
industrial revolution in the 1800s, the achievement of
physical maturity generally paralleled social-role maturity.36
Even until the early 20th century, the delay between
physical and social-role maturity was very short.
The decreasing age of onset of puberty that took place
throughout the 20th century seemed to be related to
improvements in childhood hygiene, nutrition, and
health. This trend had largely ceased by the 1960s in
high-income countries when the mean age of menarche
stabilised at about 12–13 years.37 In these countries, the
increase in the age at which adult social roles and
responsibilities were adopted began at about the same
time, which has made it less clear when adolescence now
ends. Not only do young people now spend longer in
education and marry and have children later22,38 but also
contemporary social-role transitions, such as completion
of education, employment, marriage, and childrearing,
are increasingly less defined and linear than they were
historically.38 Despite its widespread legal significance,
the age of 18 years clearly no longer signifies adulthood
in many parts of the world (panel).
The combination of children beginning puberty earlier
and taking on characteristically adult roles at an older age
than they did historically has increased the length and
indeed changed the shape of adolescence. These secular
trends, evident in all but the poorest of countries,39,40 are
further affected by regional social determinants (economic,
cultural, and political) and by risk and protective factors.
For example, in the Arabic-speaking countries of north
Africa and west Asia, high costs of marriage and secure
housing have contributed to an increase in the age at
which people are getting married.41 Additionally, increasing
industrialisation, global isation, urbanisation, and access
to digital media are reducing the influence that families
and communities traditionally had on the transition to
adulthood by decreasing parental control, social support
for families, and social cohesion. At the very least, there
seems to be less agreement between generations and
within different communities across the world about the
accepted timing and pathways to adult roles.
The biology of adolescent development
Like early childhood, adolescence is a sensitive period in
which both normative and maladaptive patterns shape
future trajectories. Part of this sensitivity relates to the
social embedding of health risks and the biological
changes before, during, and beyond adolescence.
100 years ago, puberty was widely thought merely a
process of physical maturation that propelled individuals
into different social contexts that affected their health.42
We now appreciate that puberty is a highly programmed
and biologically driven process that affects behaviour,
emotional wellbeing, and health in complex ways. For
example, the timing of puberty rather than chronological
age is most associated with the increase in health-related
behaviours and mental health states during adolescence.43
These changes in behaviour and mental health might be
partly related to changes, started at puberty, in the
regulation of oxytocin in girls and vasopressin in boys,
which have been linked to social attachment, pair-bonding,
and parenting behaviour across species.44 Although the
processes have not yet been elucidated, family and social
factors such as parental health and marital tension and
the presence of a stepfather also affect pubertal timing.45–47
There is growing interest in understanding how
puberty affects the developing brain. Animal data show
that hormonal events during puberty exert major effects
on brain maturation and behaviour that alter the
perceptions, motivations, and behavioural repertoire of
these animals and enable reproductive behaviour and
Panel: Definitions of adolescence and young adulthood
in a particular country.13
from the Latin adolescere—the present participle adolescens means?growing?up,?whereas?
the past participle adultus means?grown?up.
independence.48 Although little is known about the
relation between puberty and neural development in
people, investigators have tentatively suggested that
pubertal hormones might also affect the structure and
function of the developing human brain.48
Advances in MRI have enabled the identification of
changes in the cortical grey matter of the brain that
take place in a region-specific and non-linear manner
through out adolescence and into early adulthood.49,50
Across the frontal, temporal, and parietal cortices,
transformations of grey matter conform to an inverted-
U-shaped developmental trajectory, with increases in
volume during childhood reaching a peak in early
adolescence with a subsequent decrease in volume in
early adulthood.49,51 This trajectory is thought to arise
from dendritic outgrowth and synaptogenesis (corres-
ponding to increased grey matter volume in MRI) with
subsequent synaptic pruning (decreased grey matter
volume).52 This fine tuning of synaptic connections
provides an opportunity for brain remodelling in
response to social, emotional, and behavioural exposures,
such as substance misuse. MRI studies show an overall
increase in white matter from childhood to adolescence,
which then slows and stabilises in early to mid-adulthood
depending on the brain region in question. This
increase is attributable to progressive age-related axonal
myelination or increasing axonal calibre, both of which
enhance the speed of neuronal transmission.53
The prefrontal cortex—the site of executive control
functions, including planning, emotional regulation,
decision making, multi tasking, and self-awareness—is
one of the brain regions that undergoes the most
protracted development in human beings. The prefrontal
cortex starts to develop very early in life and continues
after adolescence until the individual is well into their
20s.49,54 This brain development might explain the
steady improvement in self-control from childhood
to adulthood. By contrast, the limbic system, which
governs reward processing, appetite, and pleasure
seeking, develops earlier in adolescence than does the
prefrontal cortex.55 The greatest disparity in maturation
between the limbic system and prefrontal cortex is during
early to mid-adolescence. Heightened risk-taking at this
time could be explained by a developmental imbalance
that favours behaviours driven by emotion and rewards
over more rational decision making.48,55
The reason why adolescents can be poor decision
makers was thought to be because they were less intel-
lectually mature; however, data suggest that adolescents
can make surprising decisions despite knowledge of
risks. Adolescents seem to be more affected than adults
by exciting or stressful situations when making
decisions—so-called hot cognitions—especially in the
presence of peers.56 Increased activity in the nucleus
accumbens—a region associated with reward, pleasure,
and other emo tional responses—seems linked to these
behaviours.57 This is consistent with the notion of
sensation seeking—the willingness to take risks to attain
new, varied, and stimulating experiences—an important
mediator for risky behaviour and which increases between
age 10 and 15 years, suggesting this behaviour is affected
by puberty.56,58 Such knowledge reinforces policies
supporting graded exposure to risk, such as a limit to the
number of passengers allowed in a car with a young
driver.59 The wider implications of the nature and timing
of adolescent neurocognitive maturation on policies and
programming are only starting to be explored.60
The effects of social context on health
Both structural determinants of health (eg, national
wealth and income inequality, access to education and
health-care services, employment opportunities, and sex
inequality) and proximal or intermediate determinants
of health (eg, connectedness of adolescents to family and
Physical developmentCognitive development Social and emotional development
increased emotional stability, concern for others, and independence and
Table 1: Developmental characteristics of adolescence and young adulthood
school) affect health-related behaviours and states in
adolescence.61 Whereas many social determinants
contribute to an individual’s health across their lifetime,
some have particular salience during adolescence. Social
determinants of health that specifi cally affect adolescents
consist of policies and environ ments that support access
to education, provide relevant resources for health (eg,
contraception), and create opportunities to enhance
young people’s autonomy, decision-making capacities,
employment, and human rights.
Similar to proximal determinants of health is the notion
of risk and protective factors. However, these operate
within the individual and their family, peers, school, and
community. By interacting with structural determinants of
health, risk and protective factors across these domains
affect adolescents’ engagement in health-related behav-
iours—both positively and negatively.24,62,63 For example,
risk factors within the individual domain that relate to
intelligence, sexual orientation, or personality can result in
negative peer relationships, such as bullying, which
increase the likelihood of various health-related behaviours,
including substance misuse, unsafe sex, depression,
antisocial and illegal activities, and dangerous driving.64,65
Thus, beyond academic achievement, schools are an
important social environment for adolescents that promote
peer connec tions, emotional control, and health. School-
based inter ventions that create strong engagement between
students and teachers and a feeling of emotional safety
result in reduced substance misuse, violence, and other
antisocial behaviours in adolescents.66 This finding is
consistent with the positive youth development approach,
which focuses on adolescents’ assets and developmental
strengths, whether internal to the individual (eg,
intelligence), or external (eg, peers and school).67,68
Together with differential protection of human
rights, the complex interaction of social determinants of
health and risk and protective factors with the biological
and social-role transitions of adolescence explains the
growing disparities between the health of adolescents in
different regions and countries. These same factors also
affect the experience of growing up within the same
country, where adolescents can have highly hetero-
geneous life experiences and diverse health outcomes. In
Australia, for example, adolescents with an indigenous
ethnic origin, from a refugee background, or who are
incarcerated or homeless have worse health outcomes
than do their mainstream peers.69–72
Changes in the adolescent burden of disease
Changes in the biological and social transitions that define
adolescence have important links to health (figure 2),
although the processes by which this happens are complex
and still not wholly understood. For example, the timing of
puberty is linked to the onset of sexual activity and the
risks of teenage pregnancy and sexually transmitted
infections.73 That adult roles and responsibilities are now
achieved at an older age in many high-income countries
also has implications for sexual health, but for different
reasons. In these countries, where the age of first sexual
inter course is about 16 years, the period of vulnerability to
sexually transmitted infections caused by premarital sexual
intercourse has extended from only a few years to more
than a decade. The heightened sensitivity to peers during
adolescence affects adolescents’ experimentation with
health-related behaviours, such as substance mis use.74,75
The timing of puberty also affects substance misuse—eg,
young people who begin drinking in early adolesence are
more likely to become alcohol dependent within 10 years
and to have lifetime alcohol dependence than those who
begin drinking at an older age.76 The increase in the length
of adolescence has also changed the importance of these
behaviours. For example, because marriage and child-
rearing contribute to the reduction in many risk
behaviours,77 the trend for people to marry and have
children at an older age is especially potent when combined
with the early onset and heavy consumption of alcohol,
which is increasingly seen in girls as well as boys.78,79
Additionally, youth unemployment, which is at very high
levels in several countries, increases the risks for substance
misuse and mental disorders in adoles cence. The
subsequent effects on social confidence, skills, and
financial resources will probably have far-reaching results
well into adulthood.
Overall, the health of adolescents has improved to a
lesser extent than that of younger children.80 In a
longitudinal study of 50 countries, childhood mortality
was reported to have declined by more than 80% in the
past 50 years.18 By contrast, adolescent mortality has only
marginally improved. A notable example is in Brazil,
where more adolescents die from violence than do
children younger than 5 years from infectious diseases.14
Figure 2: Conceptual framework for adolescent health
Puberty and social-
behaviours and states
Social, educational, and economic policies and interventions
Preventive care and health-service delivery
Although engagement in some risky behaviours might
be thought a normal aspect of adolescent develop ment,
some have immediate negative effects and many are
preventable.24 The leading risk factors for incident DALYS
in young people aged 10–24 years are alcohol (7% of
DALYs), unsafe sex (4%), iron deficiency (3%), lack of
contraception (2%), and illicit drug misuse (2%).17 At least
15% of the worldwide disease burden is accounted for by
DALYs in 10–24 year olds, which challenges the widespread
belief that adolescence is a healthy time of life.
An analysis of worldwide patterns of mortality reported
that 2·6 million young people aged 10–24 years died in
2004, with mortality increasing from early to mid-
adolescence and into young adulthood.19 The rate and
causes of death differed substantially by age, sex, and
region, with mortality rates almost four times higher in
low-income and middle-income countries than in high-
income countries. The leading causes of death were
injuries (both unintentional, such as road traffic accidents,
and self-inflicted, such as suicide); maternal causes; com-
municable, nutritional, and perinatal diseases (eg,
tuberculosis, meningitis, and HIV/AIDS); and non-
communicable diseases (such as diabetes and cancer).
Irrespective of region, most adolescent deaths are
preventable and thus strongly justify worldwide action to
enhance adolescent health. Incident disability also in-
creases with age throughout adolescence.17 The contri-
bution of mental disorders to the non-fatal burden of
disease rises sharply throughout adolescence and is the
largest contributor to the burden of disease in young people
aged 10–24 years (45%), ahead of unintentional injuries
(12%) and infectious and parasitic diseases (10%).17
Emerging drivers of adolescent health
In addition to the well established influences of parents
and peers during adolescence, various new drivers are
emerging. Marketing of unhealthy products and life styles
(eg, tobacco, alcohol, and foods high in fat, sugar, and salt)
clearly targets young people. Analogous to an infectious
disease epidemic, mass media can be viewed as a vector
that carries attitudes and products to an increasing number
of hosts, resulting in outbreaks of previously uncommon
behaviours. The extent of such epidemics results from the
relation between economic, sociocultural, and public-
policy environments.81 For ex ample, tobacco marketing to
men, and then increasingly to young women, largely
brought about the rise in smoking that peaked around the
mid-1960s in men in high-income countries, and about a
decade later in women.82 As a result of ever-tightening
policy environ ments, the tobacco epidemic is now well
past its peak in countries such as Australia, Canada, the
UK, and the USA, with substantial declines in adolescent
smoking seen over the past 15 years in these regions.
The tobacco industry is now vigorously investing in
advertising campaigns in middle-income and low-income
countries that historically had very low rates of smoking,
especially in women.83,84 Not surprisingly, these countries
are undergoing an increase in male smoking,85 with sub-
stantial yearly increases in cigarette smoking per person in
countries such as China (8·0%), Indonesia (6·8%), and
Syria (5·5%).83 Tobacco in other forms, such as smokeless
(chewing) tobacco and water pipe smoking, is also marketed
to young people86—nearly one in five of the world’s
adolescents aged 13–15 years use tobacco, and more than
one in ten use tobacco in a form other than cigarettes.87 A
major concern is the rapid rise in female smoking as
marketing and globalisation lead to a decrease in traditional
cultural prohibitions against this practice.82,85 Men are four
times more likely than women to smoke,88 whereas boys
aged 13–15 years are now only 2·3 times more likely to
smoke than girls their age,87 and in many countries sex
differences in adolescent smoking rates no longer exist.89
Young people are the earliest adopters of information
and communication technology such as mobile phones,
the internet, instant messaging, and social networking
sites including Facebook and Twitter, both in low-income
and middle-income countries as well as high-income
regions.5,14 The expanded social environment provided by
new forms of social media has both real and perceived
risks and benefits. New social media provide a powerful
voice for young people to actively engage with one another
or to circumvent more traditional and controlled forms of
media and communication. The extent to which various
governments have attempted to restrict access to new
media—such as internet censorship and restrictions to
social networking sites imposed in China,90 Libya, and
Iran—reinforces the perceived power of such com muni-
cation. Arguably, young people’s engagement with new
social media has enabled adults to appreciate the capacity
of the young to be active catalysts for community change, a
part they have long played. However, young people are
susceptible to the physical effects of intense engagement
with media (eg, decreased physical activity and sleep
disturbance), to new variations of old difficulties (eg, cyber-
bullying and pornography) and to previously unknown
behaviours, such as sexting (the act of sending sexually
explicit messages or photographs by mobile phone).
Adolescence is a sensitive time for social learning
through imitation of behaviours, especially by peers. The
ubiquitous nature of new media has arguably changed the
very notion of the peer group. Certainly, it has changed the
speed at which sociocultural norms are affected91 and has
contributed to the rise of what were previously less
common attitudes, aspirations, and behaviours.92 Social
contagion received attention more than 200 years ago as a
result of a cluster of suicides after publication of a popular
novel in which a young man committed suicide.93 Copycat
suicides are even more probable now, in view of the power
of new media to emotively and graphically publicise
suicides.94 Social contagion has been invoked as
contributing to behav iours that range from the very
uncommon (eg, school shootings95) to the more widespread
(eg, deliberate self harm96). The extent of publicity around
such behaviours further contributes to new norms.
The rising influence of social media has resulted in great
interest in how it can be used to promote the health of
adolescents, and a growing number of trials suggest
positive effects of interventions that make use of infor-
mation and communication technology.97 Population-
focused social marketing approaches seem to have
particular salience in changing community values and
attitudes in the young. For example, the South African
multimedia so-called edutainment programme Soul City
has helped change social norms about HIV/AIDS and
domestic violence, contributed to increases in individuals’
knowledge about condom use and domestic violence, and
widely contributed to the empowerment of local com muni-
ties.98 For such interventions to be effective, knowledge of
prevention science will no longer be sufficient; new skills
and alliances will be needed to exploit opportunities for
health, such as social marketing, information technology,
and creative design. One such alliance, the television net-
work MTV’s Staying Alive Ignite campaign, aims to prevent
the spread of HIV by changing attitudes, behaviours, and
national norms. Based on a confronting television drama,
the accom panying multimedia cam paign challenges young
people in Kenya, Trinidad and Tobago, and Ukraine to
ignite a wide social movement to stop the spread of HIV.
Adolescents and global health agendas
The Millennium Development Goals have driven global
health policy for the past decade. Adolescence has become
an important focus because improvement of adolescent
health is central to the achievement of worldwide targets
associated with maternal health, child mortality, and HIV/
AIDS. The Millennium Development Goals continue to
provide a very important opportunity to focus on sexual
and reproductive health, which are fundamental to im-
prove ment of young people’s health—maternal mortality
is one of the leading causes of death in adolescent girls and
young women in Africa and southeast Asia;19 more than a
third of girls still undergo child marriages;15 and adolescents
are at the heart of the HIV/AIDS epidemic (table 2).103
However, adolescents are central to the success of many
other emerging health agendas. The growing worldwide
focus on mental health is an important opportunity to
target adolescent health, because adolescence is when
many psychiatric disorders begin,118 and neuropsychiatric
disorders, including sub stance misuse, contribute to
nearly half of non-fatal DALYs in people aged 10–24 years.17
Undoubtedly, there can be no improvement in mental
health without a focus on adolescent health.
The global health agenda on injury prevention could be
used to achieve major health benefits for adolescents
because this age-group disproportionately contributes to
all-age injuries.111 Road traffic accidents, suicide and
homicide, violence and war, drownings, and fire-related
incidents account for about 40% of all youth mortality, by
contrast with people older than 25 years for whom these
injuries account for only 10% of deaths.19
The substantial rise in tobacco use in adolescents will
result in devastating effects on adult health in low-income
For more on the MTV Staying
Alive Ignite campaign see
Reasons for being a global health goalReasons to focus on adolescents
health (MDG 5)
third;100?nearly?21?million?(50%) induced?abortions?per?year?are?unsafe;101 complications
but?less?than?one?in?three?of?them?use?effective?contraception;100 in sub-Saharan Africa,
accounting?for?41%?of?new?infections?in?those?older?than?15?years;103 HIV/AIDS is the
spread of HIV
Respond to the
disorders in their lifetime105
Respond to the
Respond to the
Table 2: Examples of global public health goals and the contribution of adolescence
and middle-income countries for many decades.85 The
success of tobacco control policies that focused on access
(eg, pricing and taxation) emphasises that many
interventions promoting adolescent health are the result
of population-targeted campaigns.24 Urgent implemen-
tation of the Global Framework Convention on Tobacco
Control119—a treaty to reduce the availability of, and
interest in, tobacco for young people—is necessary.
The rising burden of non-communicable diseases has
resulted in an increased worldwide focus on tobacco
control and other risk factors for adult disease, such as
obesity, low levels of physical activity, and alcohol
consumption.26,27 Policy resonance is being driven mainly
by arguments about the worldwide burden of non-
communicable diseases, which now account for two in
every three deaths, including in low-income and middle-
income countries,120 and about the efficiencies that could
be achieved by clinically oriented secondary prevention
interventions targeting common risk factors in
adults. Despite the estimation that 70% of premature
deaths in adults are largely caused by behaviours started
in adolescence that share common risk factors,1
little articulation has taken place within the non-
communicable disease agenda about the importance of
adolescents as a target for universal prevention.
Recognition of adolescent health
Within child health, decades of clinical experience have
stimulated research that has in turn affected national and
global public policy, public health, and models of clinical
practice within key domains of interest (eg, infant
mortality and pneumonia). These efforts have contributed
to the growth and integration of child public health.
Collaborations, networks, advocacy, and funding
organisations that stretch beyond health have resulted in
national and worldwide investment and initiatives that
have led to substantial improvements in child health.
Adolescent health is a much younger discipline by
comparison. Although the International Pediatric
Association was established in 1910, the International
Association of Adolescent Health was not established
until 1987. In many low-income countries, the life stage
of adolescence is only just being recognised.39,121 In the
USA, adolescent medicine emerged as a distinct medical
specialty about 50 years ago and has contributed to
improvements in clinical practice, public health, and
prevention science.122 Other high-income countries have
only very recently adopted adolescent medicine as a
specialty, which explains why many health professionals
have insufficient training and skills to work effectively
with adolescents.123,124 The training needs of clinicians and
public health practitioners in low-income and middle-
income countries are only starting to be appreciated.121,125
The current generation will take a different path
through their adolescent years from previous generations
and will face new challenges to their health along the
way. How they negotiate these years will have a powerful
effect on their future health and their countries’ economic
and social prospects. We make the following recom-
mendations to promote the health of adolescents and to
ensure that adolescence is indeed a strong foundation for
Embrace adolescence within the life course
What happens during adolescence is central to many
emerging global health agendas. In view of this promin-
ence, these agendas are unlikely to be successful without a
greater focus on adolescence. Even when the contribution
of adolescents to the wider agenda is indisputable, such as
in international HIV/AIDS initiatives, it is often overlooked
in terms of policy and programming. To rectify this
omission, much greater appreciation of the importance of
adolescence within a life-course perspective is needed.
Develop a cross-cutting agenda
Social determinants of health that are distinctly influential
during adolescence combined with common risk and
protective factors suggest that efforts to improve health
issues will probably be effective if they are part of a cross-
cutting agenda focused on adolescent health as a whole,
rather than in terms of different diseases. An international
agenda on adolescent health would place the developmental
phase of adolescence centre stage rather than any one
health issue, but would build on and contribute to the
interventions taking place within distinct disease entities
(so-called vertical silos). This agenda would focus attention
on the common determinants of health that promote both
risk and protective factors in young people’s lives. It would
also promote the implementation of adolescent-friendly
health systems and services that are able to effectively
respond to the specific needs of young people.4,126 Import-
antly, it would support investments in preventive inter-
ventions that extend well beyond the health sector24,127
through alignment with education, employment, sex
equality, and human rights initiatives.
Make adolescents and their health visible
Good information systems are an important step
towards making adolescents and their health more
visible to policy makers, researchers, donors, and
development partners. The insufficient prominence of
adolescent health could be a result of inadequate
information systems,128,129 which shows inadequate
acknowledgment of adolescence as a developmental
stage and a failure to appreciate the dynamic nature of
health across adolescence. No doubt, this is compounded
by incon sistent age definitions—eg, age categories that
view young people aged 15–19 years as adults (eg,
0–14 years, 15–64 years) effectively render adolescence
invisible, and are usually inconsistent with the age
criteria of relevant services such as health and
education.130 The value of reporting data for three
categories across adolescence (10–14 years, 15–19 years,
and 20–24 years) is clear from publications that have
raised awareness of the greatly changing health profile
across this developmental period.17–19
Give adolescents a stronger voice
Greater engagement of young people, whether as
consumers of health services or recipients of preventive
intervention programmes, will help to ensure the relevance
of interventions that set out to target this diverse population.
If adolescents are given a voice by being involved in the
identification of their health issues and development of
appropriate solutions, they will also be more visible to their
communities, stakeholders, and decision makers.
Increase the capacity of the specialty
Despite growing worldwide interest in adolescent health
and medicine,4,5,14,15,25 local, national, and global capacity is
insufficient to shape the necessary attitudes and skills of
the next generation of public health practitioners,
prevention scientists, policy makers, and clinicians.
Functional capacity will be provided by greater invest-
ments in people and organisations.
Funding to support the development of academic
centres of excellence in adolescent health, such as the
Leadership in Adolescent Health programme in the
USA,25 is necessary to develop sufficient public health,
prevention science, advocacy, and policy skills within
adolescent health. This development would foster
proficiency within the major categories of adolescent
public health (eg, sexual health, tobacco use, substance
misuse, mental health, and injuries). A strong focus on
adolescent health within undergraduate and postgraduate
health programmes is urgently needed, as is reorientation
of existing professionals to the specialty.
Achievement of the necessary worldwide invest-
ments in adolescent health would be greatly aided by
more visible advocacy efforts, especially in relation to
governments, donors, and development partners. In the
short term, reorientating child-health advocacy groups to
be more inclusive of adolescents would be helpful,
but in the medium term, more focused initiatives on
adolescents are needed.
SMS conceived the paper as part of the planning of the Series on
adolescent health, and led the writing of the paper, which all other
authors contributed to. SMS and GCP led the development of the
Conflicts of interest
We declare that we have no conflicts of interest.
We thank David Bennett, Bob Blum, Chiara Bucello, Carolyn Coffey,
Louisa Degenhardt, David Hawkins, and John Santelli for their
contributions to this report.
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