The world now has more young people than ever before – of the 7.2 billion people worldwide, over 3 billion are younger than 25 years, making up 42% of the world population. Around 1.2 billion of these young people are adolescents aged between 10 and 19 years.


Adolescence is a critical time of life. It is a time when people become independent individuals, forge new relationships, develop social skills and learn behaviours that will last the rest of their lives. It can also be one of the most challenging periods.


In this turbocharged neurological, physical, and emotional transition from childhood to adulthood, young people face a range of health risks. They are often exposed to harmful products such as tobacco, alcohol and drugs, they face greater risks of violence (including homicide) and road traffic injuries than in childhood, and can experience devastating mental health issues such as depression, anxiety, self-harm, substance abuse and addiction to video games, as well as eating disorders and suicide. Young people can also face sexual health issues such as sexually transmitted diseases or teenage pregnancy.


Many of these issues are linked to wider societal determinants and social norms. For example, pressures to conform to ideals about body image, normalization of recreational drinking in media, social exclusion, challenges in accessing support services, coupled with rapid physiological and neurological changes and the urge for exploration and experimentation, can make it hard to cope with the varied challenges that today’s youth will almost certainly encounter.


Depending on where they live in the world, young people may face an even wider range of threats to their health, including racial or gender discrimination or violence, human rights violations, conflict or social disruption from natural disasters, being overweight or obese, female genital mutilation (FGM), forced child marriages or sexual exploitation and abuse. 


The numbers are striking: about 3000 adolescents die every day; in 2016, more than 1.1 million adolescents aged 10-19 lost their lives, mainly to preventable causes such as road injuries, complications of pregnancy or giving birth, or because of HIV/AIDS.


Adolescent health is starting to attract the attention it deserves, and is increasingly prominent in global health initiatives. This includes the Global Strategy for Women’s, Children’s and Adolescents’ Health, areas such as mental health (young people’s mental health is the theme of 2018’s World Mental Health Day on 10 October) and management of sexually transmitted infections (growing rates of infections in adolescents was much discussed at the 2018 International AIDS conference in Amsterdam).


Yet, a comprehensive approach to adolescent health is often lacking, with this critical age group very much at risk of being left behind in the development agenda. “For a long time there has been an assumption – sustained by critical gaps in data – that adolescents are healthy.


Most of them indeed are, but much less so than we used to think. Data show that the considerable gains from investments in maternal and child health programmes are not sustained in adolescence: the reduction in child mortality was not mirrored by a similar reduction in adolescent deaths,” says Dr Princess Nothemba (Nono) Simelela, WHO’s(World Health Organisation) Assistant Director-General for Family, Women, Children and Adolescents.


“Youth are central partners and collaborators because of their inherent strength to create change. WHO remains committed to meaningfully engage youth in our work and to implement youth lens in our planning and actions,” says Ms Diah Saminarsih, WHO’s Advisor on Gender and Youth.


A new WHO report on youth, health and development launched this week articulates how adolescent global and national leadership could be institutionalized and actively supported in WHO’s work with Member States and a diverse range of partners, including groups led by young people, to embed engagement with young people in every aspect of the health ecosystem.


The report refers to young people as a “powerhouse of human potential” and describes strategic opportunities to meaningfully engage them in transforming health and sustainable development. Young people can be critical agents of change, it says, if they are allowed to be part of the conversation in a fundamental way.


“With over 40% of the world’s population under the age of 24 years, young people have to be part of any meaningful solution to the world’s challenges—and this is their right. Ensuring young people’s meaningful, safe and effective engagement for health and sustainable development is a matter of urgency for Member States, WHO and partners, and young people themselves,” says Dr Shyama Kuruvilla, in WHO’s department for Family, Women’s and Children’s Health.


As boys and girls enter adolescence, health risks become increasingly skewed along gender lines. Some of the differences are biological, such as complications from teenage pregnancy or being at risk of being infected with human papillomavirus (HPV) that can lead to cervical cancer later in life – but many are shaped by societal gender norms such as expectations on girls to get married or on boys to earn an income at an early age.


Violence is one of the biggest threats that young people face – and much of this violence happens between peers. In the past year alone, one billion children worldwide – over half of all young people aged 2–17 years – have experienced emotional, physical or sexual violence. Both boys and girls experience high levels of violence, and policies developed need to be appropriate for the types of violence faced. 40% of 13-15 year olds were involved in a physical fight in the past 12 months.


Violence has a strong gender component: one in five girls under the age of 20 report experiencing sexual violence, compared to 8% of boys. Girls are more likely to experience sexual or physical violence from partners, or be forced into child marriage, trafficking, child labour, or genital mutilation.


Boys are more likely to be both victims and perpetrators of homicide, involving weapons such as firearms and knives: homicide is among the top five causes of death in adolescents, and males comprise over 80% of victims and perpetrators. Boys are also more likely to be in road traffic accidents, which can cost them their lives.


Social and economic inequalities always have a detrimental effect on health, and nowhere is this more apparent than with young people. Adolescents from ethnic minorities, refugees, young offenders, people who identify as LGBTQIA+, may face greater health challenges, including mental health problems, disabilities, or autism spectrum disorders, in part due to stigma, social exclusion, discrimination and rejection by their family or community.


“Social norms affect young people, whether they are rich or poor. A classic example is attitudes to menstruation in India, which can lead to the ostracization of girls from educational or social activities with lifelong repercussions, and barriers to fact-based sexuality education (especially for girls) in a number of countries,” says Dr Venkatraman Chandra-Mouli, Reproductive and Sexual Health Specialist at WHO.


Adolescence is a highly formative time for future health. While many of the challenges that emerge at this age are rooted in experiences in the womb or in young childhood, effects of the neurobiological changes in the very early years can emerge in adolescence. This will influence behaviours that can lead to heart disease and other chronic conditions that also tend to be established at this crucial time of life, including levels of physical activity, nutrition, tobacco smoking, and alcohol use. Most smokers start smoking when they are teenagers – one in two people who start and who continue to smoke will be killed by tobacco-related illnesses.


Risky behaviours can begin as experiments but then become lifelong habits, with profound implications for health and well-being


The impact of such health issues can affect not only current youth, but also future generations. If young people are exposed to violence, they are in turn more likely to perpetuate it themselves. Meanwhile, mental health issues that develop in adolescence can affect the way people later parent their own children, incurring potential consequences for generations to come.


“Half of mental health disorders arise before the age of 14,” explains Dr Tarun Dua, mental health expert at WHO. “If these are left untreated, they extend into adult life, thus impacting educational attainment, employment, relationships or even parenting.”


Self-harm is the third leading cause of deaths in 15-19 year olds. 80% of depression begins in adolescence, but many cases go undetected and untreated.


Moreover, many unhealthy behaviours and health conditions are interlinked. For instance, bullying can lead to self-harm, eating disorders, or anxiety disorders that can persist throughout their lifetime, as well as making it more likely that a young person will have suicidal thoughts.


The converse can also be true, however. Although this period of life can be fraught with difficulty, there is also an enormous opportunity to protect future health. Often for the first time, young people will be making independent decisions about what to eat and how much, whether to do regular sports and exercise, whether to engage in safe or unsafe sexual practices, or whether or not to try addictive substances such as drugs or alcohol.


Thus, positive development is critical for young people, in particular learning specific social skills, being able to form bonds with other people, developing a sense of self-worth, gaining a sense of right and wrong, and building the ability to empathise with others.


“Some adolescents will make healthy choices but some will start making unhealthy choices. These may start as experimental behaviours, but without adequate support can become lifelong habits. The challenge for us is to design policies that will make healthy choices easy, and unhealthy choices difficult, expensive and inaccessible,” says Baltag.


When young people are protected by age-appropriate policies and programmes, and given safe spaces in which to not only survive but actually thrive, they can develop resilience that ensures they grow into healthy, well-adjusted adults. Effective interventions at this time, will therefore yield lifelong benefits and longlasting returns.


A particular challenge in addressing risks that young people face is that prohibitive approaches (e.g. laws restricting the sale of alcohol and tobacco use) do not always work without adequate family and societal support and protection. The widespread availability of pornography coupled with a lack of adequate sex education in many countries can mean that young people are not aware of risks they may face, or understand healthy sexual behaviour. Education (both at home and at school) is critical in teaching young people how to behave responsibly.


“Sexuality education is about much more than talking to young people about sex and condoms, but rather aims to prepare young people for a healthy, and a pleasurable sexual and reproductive life,” explains Chandra-Mouli. “There is ample evidence from countries around the world that well-designed, well-delivered sexuality education programmes do good and do not result in harm, that they improve knowledge and understanding, promote positive behaviours and when combined with a healthy dose of gender, actually reduce health problems such as unwanted pregnancies and sexually transmitted infections.”


Young people navigate almost every element of their lives, especially their social lives, through technology. While it can sometimes lead to obsessive behaviours such as internet or gaming addiction, technology can also be a way to provide them with such critical information, connect them with services or empower them in their own healthcare. For example, digital health programmes about sexual health, physical activity or diet; or providing adolescents the ability to provide confidential online feedback to health providers on their experience with care.


As well as facing numerous health challenges, however, too many young people continue to face significant barriers to accessing healthcare, either because they live in remote areas,  are too far from health services, lack independent income, or feel that existing services – often tailored more to women and young children – do not meet their needs. Stigma can also be a significant barrier to accessing mental or sexual health services.


Investing in adolescent health

Many of the health challenges that young people face – noncommunicable diseases, violence, road traffic accidents – are set to rise as the world continues to become more crowded, more urban, and more mobile. Increasing exposure to tobacco, drugs and alcohol via the internet and the media, and ever-increasing marketing of unhealthy products to young people, is ensuring that young people continue to be at risk of obesity or alcohol or substance abuse at a time when they are most vulnerable, and when their bodies are still in crucial phases of development. The need to invest in the health of adolescents has become urgent.


“Investing in the health and well-being of adolescents, especially adolescent girls, should be a top priority for national and international policymakers. These investments are not only the right thing to do, they also yield tremendous economic and social returns and are vital to achieving the global sustainable development agenda,” says Dr Natalia Kanem, Executive Director, UNFPA.