A second chance in the second decade

What determines differences in health and disease?


Key points

  • Determinants make clear which interventions are most likely to influence health and health-related behaviours.
  • Determinants can either increase risk or protect and promote health.
  • A wide range of determinants affects health status, from individual characteristics to social norms and policies.
  • Social determinants of health and health-behaviours may be particularly important during adolescence.
  • Environmental and individual determinants interact in complex ways.
  • Determinants have implications for policy-making and programme design.

Determinants of health and health-related behaviours

With variations in timing and duration, all adolescents experience similar biological, cognitive and psychosocial changes that affect their health and health-related behaviours. Section 2 discusses these changes and their impact. However, as Sections 3 and 4 show, there are important differences between and within countries in the major causes of adolescent mortality and morbidity and the prevalence of health-related behaviours. This section explores some reasons for these differences and the implications for interventions.

Health and developmental outcomes during the second decade of life are affected by many of the same factors that improve or undermine the health of adolescents’ families and communities. A recent analysis that explored the impact of social determinants on adolescents’ health found strong associations between factors such as socio-economic and educational status and a range of health outcomes, including adolescent pregnancy and a number of health-compromising behaviours.1

Viner R et al. Adolescence and the social determinants of health. The Lancet, 2012, 379(9826):1641–1652.

Social determinants may influence health in different ways across countries, however; a determinant may be linked with higher prevalence of health-compromising behaviours in some countries, but lower prevalence in others. For example, in the Health Behaviour of School-Age Children Survey, higher affluence was associated with daily consumption of sweetened soft drinks in Armenia and Turkey, among other countries, while it is associated with lower prevalence among adolescents in Iceland and France.

Links between relative affluence and decreased risk behaviours from HBSC data

Daily consumption of soft drinks

Fighting three of more times in the last 12 months

Agree that classmates are kind and helpful

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A life-course perspective

What happens during the first decade of life has important repercussions on many aspects of adolescents’ health and development: the cumulative impact of social determinants; the long-term effects of adverse childhood experiences and stressors, such as violence and abuse; and disease, disability and poor nutrition that starts during the early years of childhood. All these affect adolescents’ growth and puberty, health and development, including mental health,2 3health-related behaviours4 5 and the development of competencies and assets.6 The growing understanding of the importance of epigenetic influences on health and disease is providing new insights into the ways that these determinants play out across the life-course.7 8

Interventions during early childhood, and even before conception and during pregnancy, are therefore central to a life-course approach to adolescent health. Such interventions are not the focus of this report, however, which is limited to interventions implemented during the adolescent years.


For similar reasons, this report also does not focus on interventions directed to the health implications of delayed social transitions, such as family formation and work, which increasingly take place during the third decade. However, when these transitions take place during the adolescent years, they are important determinants of poor health. Early marriage, early pregnancy and work, particularly during the early years of adolescence, are obvious examples.

Adolescents on what makes them feel safe: Knowing that my family and friends are there supporting me and that their reasons for not letting me do something is because they care about me or feel like I can do better.

18-19, Female, Thailand

I have a group of very close friends who looked out for me when I needed them most. I then talked to my parents and then saw a doctor about my situation. Since then I have been much happier and more content.

male, 15-17, United Kingdom

Adolescents on what makes them sad: To see the situation not only in my city but in my country. To know that in my city the government can’t finish a simple public transportation project. Not being able to walk the streets without being in fear.

female, 15–17, Mexico

Adolescents on what can be done to improve their health: Intervene and inform us more, create a web site where we can talk online with a psychologist, nurse, doctor, etc. Especially on the Internet and Facebook, as we are young and we tend to use these technologies very often.

female, 15–17, country not specified

I feel like I am safe when I am at school.

12-14, female, Malawi

My country is poor, especially in this post-conflict era, and there are many risks to my health. Daily life is costly, and health care is difficult to access

male, 18–19, Burundi

Adolescents on what makes them sad: The situation in my country. To not have a way to get products that are very important like medicine, food and hygienic products. Injustices and unemployment.

female, 18-19, Venezuela

Adolescents on what makes them feel safe: To see that the results of my efforts are becoming reality for myself and for others.

female, 18-19, Peru

Adolescents on what makes them feel safe: Having confidence in myself and in my potential.

male, 15-17, Venezuela

My culture/environment does not encourage exercise. For instance, housing areas are not fit/safe/appropriate for a morning jog.

female, 18–19, United Arab Emirates

The support, presence, tenderness, trust and above all the love of those close to me make me feel safe.

female, 15-17, France

The conditions in my country are so unsafe that I couldn’t just take a leisurely walk or do any sort of exercise outside, like running.

female, 18–19, Venezuela

Adolescents on what can be done to improve their health: To protect the development of my country.

male, 18–19, Democratic Republic of Congo

I usually procrastinate homework, and I have gotten into an habit when I "need" to do something funny and relax on my iPhone 30 minutes before I sleep. This combined leads to a habit where I go to sleep late

female, 15–17, Norway

I get sad when I see indigenous people begging on the street, sick with skin diseases like vitiligo, breathing the dirty, smoggy air that they’re exposed to all day under the hot sun, to see other people begging for food, seeing that they’re dirty and sometimes mentally ill, begging to no avail and being exposed to the difficult life on the streets.

female, 18-19, Mexico

I often use websites that allow for anonymous communication.

male, 18–19, Canada

I am currently drinking water from the well and we share with animals, my mosquito net is torn and I do not have money to buy a new net and drought has hit our area and am not eating well balanced food.

male, 18–19, Uganda