Keywords

1 Introduction

The UK population is relatively ‘young’ and has high rates of fertility compared with most European countries, for instance 17.8 % of the total population are under 15 years of age, compared with the average for the European Union at 15.6 % (OECD 2014a), and this is mirrored by the fertility rate which in 2017 was 1.74 in the UK compared with the EU average of 1.60 (OECD 2014b). On a global footing the UK fares well along with other high income country settings on broad indicators of adolescent wellbeing, such as the WHO and UNICEF ‘flourishing index’ which includes markers of growth and nutrition, educational attainments, reproductive freedom, exposure to violence and mortality. In a recent report, using this measure of flourishing, the UK was ranked tenth behind Norway, South Korea, Netherlands, France, Eire, Denmark, Japan, Belgium, Iceland and on an equal footing with Germany, Switzerland, Singapore, Luxembourg and Sweden (Clark et al. 2020). Adolescent health has long term consequences for wellbeing and functioning throughout the lifecourse, for instance, the bulk of mental health conditions emerge during this time, and obesity along with certain habits and health behaviours tend to track from adolescence into the adult years. Today’s young people are tomorrow’s workforce and parents, and this, taken together with lifecourse implications, highlights the importance of supporting the development and maintenance of health during this phase of life.

Overarching influences on young people’s health include the social determinants and the forces of commercial marketing, both of which pose major challenges for societies. The last decade of austerity measures in the UK has seen sweeping cuts to youth services and support for educational provision. These cuts have been accompanied by widening inequalities in poor health outcomes and increases in youth violence. Two recent high profile reports (Royal College of Paediatrics and Child Health 2020; Marmot et al. (2020)) have called for the social determinants of health to feature centre stage in all government policy, arguing that health should be positioned alongside economic productivity to reflect societal success. Young people are exposed as never before to commercial marketing pressures from corporate powers including for tobacco, alcohol, sugar sweetened beverages, gambling and social media, and there is widespread inappropriate use of personal data. Clearly, governments need to protect children from harmful commercial behaviour, but this requires agile regulation which is often opposed by powerful lobby groups and well-resourced lawyers. Currently, in the UK, legislation on protecting children from commercial harms is largely absent (Clark et al. 2020).

While the picture described in this chapter is of a pre-Covid19 context, it is conceivable that aspects of health such as mental health and health behaviours will be adversely affected in the short term and beyond by the current pandemic. Furthermore, there are likely wide ranging implications for the development and implementation of policies aimed at improving and supporting young people’s health and wellbeing. For instance, it seems likely that the period of austerity experienced over the last decade will deepen even further. This chapter describes patterns of health conceptualised broadly in line with the WHO definition, as a state of physical, mental and social wellbeing and not merely the absence of disease or illness, (WHO 1946) including mental health, overweight and obesity, health behaviours and aspects of social relationships.

2 Mental Health and Wellbeing

Youth mental health is a major public health concern, which poses substantial societal and economic burdens globally (WHO 2013). Decades of underfunding in research, prevention strategies and effective treatment have resulted in unprecedented unmet need among young people in the UK (House of Commons Education and Health and Social Care Committees 2018). The UK does not compare well with other countries when considering young people’s mental health and wellbeing, for instance recent Programme for International Student Assessment (PISA) survey findings show that the UK was ranked relatively low among Organisation for Economic Co-operation and Development (OECD) countries on feelings of sadness, fearfulness, and joyfulness (OECD 2019). According to the most recent figures for England, one in eight children and young people age 5 to 19 have mental health problems including anxiety, depression, conduct and hyperactivity disorders (NHS Digital 2018a), and it is estimated that about one in four girls and one in ten boys aged 14 have clinically relevant depressive symptoms (Kelly et al. 2018). Adolescence is widely regarded as a particularly vulnerable time for the development of poor mental health with 50 % of problems emerging by age 14 (WHO 2013). Alongside this, a general deterioration in mental health and wellbeing has been observed over the adolescent period for both young women and young men (Department of Education 2019), and it is estimated that 75 % of lifetime mental health problems develop before the transition from adolescence into adulthood (McLaughlin and King 2015; Kessler et al. 2007).

There have been significant changes over time, with secular trends since the late 1990s suggesting a worsening in mental health among British youth (NHS Digital 2018a; Collishaw et al. 2004; Ross et al. 2017). A recent paper compared mental health problems in two birth cohorts born a decade apart, in the early 1990s and 2000s and suggested that clinically relevant depressive symptoms in 14–15 year olds had doubled for girls (12.4–24.0 %), increased by more than half for boys (5.7–9.2), and the proportion experiencing self-harm had increased by a third for girls (16.9–22.8) and by a quarter for boys (6.9–8.5) (Patalay and Gage 2019). The burden of poor mental health is unequally distributed and this begins early in life (Kelly et al. 2011): data from the UK Millennium Cohort Study show that young people from economically disadvantaged groups tend to be worse off compared with their more affluent peers. For instance, Figure 1 shows that approximately 20 % of girls in the richest income group have clinically relevant depressive symptoms compared with 25–30 % of those in the poorest groups, and although levels of depressive symptoms are lower in boys, similar socioeconomic patterns are observed.

Fig. 1
figure 1

Prevalence of clinically relevant depressive symptoms (age 14) by family income (own illustration)

Full size image

Many factors have been proposed to influence young people’s mental health including the importance of school, friends, family, appearance and use of leisure time (Department of Education 2019). However, the underlying reasons for observed inequalities, and overall worsening in mental health among British youth are not well understood, nevertheless, a range of explanations have been proffered relating to changes in the contexts of young people’s lives, including more time spent engaging with digital technologies, increased exam pressures and educational expectations, uncertainty about future employment and housing prospects, climate change and given the current pandemic the prospect of new emerging infections may become important. The contribution of these in relation to young people’s mental health and wellbeing are supported to varying degrees by extant research.

Young people are growing up in a rapidly changing digital age characterised by seamless transitions across multiple forms of media including TV and movies, social networking and gaming sites. Undoubtedly the benefits of digital technology use are wide ranging, for example, improved knowledge acquisition and social connectedness with geographically dispersed support networks. On the other hand, the observed decline in mental health has coincided with ubiquitous digital technology use and has led to growing concerns about the potential pitfalls of how, where, when and why people engage in digital activities. This has led to a flurry of research but questions remain, for instance about the directionality of observed associations (is it poor mental health that leads to problematic use, or vice-versa?), and about the potential for vulnerability of young people from marginalised groups (Kelly et al. 2018; Booker et al. 2018; Odgers 2018). Social relationships are important throughout the lifecourse, and in the transition between childhood and adolescence friends and peer groups become more important influences on individual behaviours and experiences. A recent report indicated that young people’s levels of happiness with their friendships has dropped over the last decade (The Children's Society 2019), and studies suggest that loneliness and social isolation are becoming more common in young people (Lasgaard et al. 2016). The ways in which use of digital technologies, on and off line relationships and experiences, and school engagement combine to influence young people’s mental health are currently a major focus for research.

Mental health policy

There is a substantial unmet need for mental health provision across the UK with only one third of young people who need it receiving treatment (NHS Digital 2018a). The most recent policy developments laid out in Transforming children and young people’s mental health provision position educational establishments in the front line role of promoting and protecting children and young people’s mental health and wellbeing (House of Commons Education and Health and Social Care Committees 2018). This policy initiative proposes to improve the timeliness and quality of care by having a designated member of staff who has a lead role for mental health in every school and college, by having mental health support teams linked to groups of schools and colleges, and by trialling reduced waiting times for specialist care services. It is envisaged that initiatives will be rolled out in Trailblazer projects with 20–25 % coverage by 2022/2023. However, the policy has attracted a significant amount of criticism on several fronts, including for failing to recognise the extent of fragmentation in service provision, a lack of joined up thinking and effective coordination across Government Departments such as Health, Education, Justice and Culture (House of Commons Education and Health and Social Care Committees 2018). Specifically the Government’s current stance fails to look at contributory factors for poor mental health and preventive strategies, it does not take account of marginalised groups, it puts pressure on already overburdened teaching professionals without appropriate allocation of resources, it fails to invest in the health professional workforce that is needed and it does not address the transition into adult care (Care Quality Commission 2017).

3 Obesity and Overweight

Overweight is associated with poor health and lost productivity throughout life and is currently estimated to cost 3 % of UK GDP, equivalent to £60B in 2018 (McKinsey Global Institute 2014; The Chief Medical Officer 2019). The public health importance of overweight is substantial, being predictive of poor physical and mental health at all life stages, including early puberty (Kelly et al. 2016a), poor psychosocial wellbeing in adolescence (Kelly et al. 2016b), non-communicable disease risk and early death (Di Angelantonio et al. 2016). The most recent data for England commissioned by the Department for Health and Social Care show that over a third of 11–15 year olds are classified as overweight including obese (NHS Digital 2018b, 2018c), important to note here is that national level data collections classify overweight and obesity according to British growth curves derived in 1990. More recent and globally comparable reference values generated by the International Obesity Task Force (IOTF) (Cole and Lobstein 2012) provide more conservative estimates of the proportion of children and young people classified as overweight or obese. Applying IOTF cut-points to nationally representative data from the UK Millennium Cohort Study shows that over a quarter of 14 year olds are overweight (including obese) and approximately one in twelve are obese (Table 1). Recent decades have seen increasing rates of overweight and obesity and this has largely been attributed to environmental changes over the same period often referred to as the obesogenic environment which fosters conditions in which people consume more and move less than we did before. The obesogenic environment exerts its influence via multiple aspects of people’s lives from structuring individual behaviours including what and how much we eat and drink, and the amount of exercise we get through to broader determinants such as the communities in which people live—their proximity to food outlets and recreational facilities, and commercial sector regulation. These influences are not evenly distributed, for example, poor diet and low levels of physical activity are more common among families living in disadvantaged circumstances (Goisis et al. 2016). Perhaps unsurprisingly then, stark inequalities in obesity are evident, these start early in childhood, and continue to widen, for instance, data from the Millennium Cohort Study show at the start of adolescence a three-fold difference in the prevalence of obesity for those in the poorest income quintile versus the richest, and by age 14 the gap has widened further to a four-fold difference (Goisis et al. 2016 and Fig. 2). Moreover, inequalities are worsening over time, the gap for young people living in the least and most deprived areas of England having widened by a further 50 % over the last decade (NHS Digital 2018b).

Table 1 Markers of health among 14 year olds from the UK Millennium Cohort Study (own illustration)
Full size table
Fig. 2
figure 2

Obesity (odds ratios) by family income quintiles, poorest vs. richest (own illustration)

Full size image

Obesity policy

The British Government’s ambition is to halve obesity rates by 2030, however, given their current action plan, this stated desire has been roundly criticised as unachievable, most notably by the Chief Medical Officer for England (The Chief Medical Officer 2019; HM Government 2018; NHS 2019). Rising rates of obesity and socioeconomic inequalities in obesity over recent decades has coincided with an increasingly obesogenic environment in which opportunities for burning energy have diminished, whilst those for consuming energy dense food and drink have skyrocketed. Inequalities are perpetuated at least in part by the substantial price gap between more and less healthy foods, with healthy foods costing 3 times as much as less healthy foods per 1000 kcal, and evidence suggesting that healthy foods are becoming more expensive over time (Jones et al. 2014).

The fact that obesity levels show little sign of reducing has led some to assume the epidemic is a somewhat intractable problem. However, the challenge has been created by societies themselves, influenced by powerful commercial interests at the cost of public health. There is widespread suspicion of a lack of political appetite for high level interventions requiring increased regulation and the potential to harm commercial interests (Adams et al. 2016; Vallgårda 2018). A major problem many societies, including the UK, face is one of identifying where changes need to be made and taking steps to affect change, and unfortunately, the British Government has historically aimed the bulk of its interventions at low level downstream factors. Currently in the UK, with the exception of the sweetened drinks levy, there is an absence of high level ‘upstream’ interventions aimed at reducing obesity and associated socioeconomic inequalities. Instead policies focus on individual ‘downstream’ behaviours and firmly place responsibility for changing behaviours with young people themselves, their parents and carers (Vallgårda 2018; Hillier-Brown et al. 2014). This approach is problematic and has not worked to reduce levels of obesity or inequalities. The central challenge here is that behaviour change typically requires high levels of agency, as the amount of agency and resources that individuals possess influences how well they benefit from interventions aimed at changing behaviours. What makes high level upstream interventions such as reversing the erosion of safe public spaces and limiting the availability of low cost energy dense foods more attractive is that they are examples of changes that require low levels of individual agency, and it is these sorts of interventions that could be the most effective and potentially most equitable (Adams et al. 2016). Interestingly, a recent opinion poll suggested that an overwhelming majority of the British public would support upstream initiatives aimed at reducing obesity, with three quarters of people agreeing that healthy food should be cheaper than unhealthy options, that there should be reduced exposure to marketing of unhealthy foods, that the sugar content of food should be reduced, and that there should be reduced concentration of fast food outlets near to schools (Savanta ComRes 2015). This evidence of the public’s enthusiasm for change highlights a clear disconnect between public opinion and action from decision makers at national and local government levels and underscores the fact that considerable political resolve will be required if we are to be successful in tackling the current epidemic.

Achieving the Government’s stated target will require wide ranging action from multiple stakeholders, including physical, commercial and environmental interventions such as the creation of safe public spaces, limits on the availability of low priced calorie dense foods, and making ‘healthy’ food options more affordable (The Chief Medical Officer 2019). One initiative being piloted in selected London Boroughs is the formation of ‘School Super-zones’ which have a mix of upstream and downstream level interventions, including: the ending of child poverty; the creation of more active, playful streets and public spaces—making it safe to walk or cycle to school, along with making free London water available; stopping the marketing and incentivising of unhealthy food and drink; and the transformation of fast-food businesses by rebalancing of food and drink sold making healthy options more attractive. At the time of writing this initiative remains in its infancy and implementation will be at the local level rather than the rolling out of a ‘one size fits all’ scheme. Consequently, the evaluation of School Super-zones will be highly complex and multi-faceted, and it is likely that there will be lengthy delays before any potential benefits are revealed.

4 Health Behaviours and Activities

In tandem with the myriad developmental changes occurring during adolescence, are an increased sense of autonomy, agency and the formation of various aspects of identity. In keeping with this perspective, adolescence is widely viewed in the ‘western tradition’ as a time of experimentation particularly in relation to various health behaviours such as alcohol consumption, smoking and drug use in addition to the exploration of intimate relationships and changes in social networks more broadly. It is also a time of profound change in aspects of physical activity, sleeping patterns, leisure time activities, and digital technology use.

4.1 Drinking, Smoking and Drug Use

In the UK over recent decades there have been dramatic reductions in the proportions of young people who drink alcohol, smoke and take illegal drugs, for example in the late 1990s just under half of 11–15 year olds had ever smoked and this had fallen to 16 % by 2018 (NHS Digital 2019). Table 1 shows percentages of 14 year olds from the Millennium Cohort Study who reported to smoke, drink alcohol and use drugs. Approximately one in six had ever smoked cigarettes or had ever vaped, and there was some evidence of gender patterning with girls more likely than boys to have smoked (18.5 vs. 15.4 %), but interestingly, girls were less likely to have vaped (16.4 vs. 18.7 %). The most recent SDD survey figures suggest that about 5 % of 11–15 year olds are current smokers, and that 6 % can be classified as current vapers (NHS Digital 2019). Data from the Millennium Cohort Study suggest no clear gender differences for drinking or for drug use, about a half of 14 year olds had drank alcohol and approximately one in ten had experienced binge drinking—having had 5 or more drinks on a single occasion, and approximately one in twenty reported having taken illegal drugs (Table 1). There are, in the main, similarities with recent estimates of drinking, smoking and drug use from other contemporary national level surveys, where there are variations this is likely due to differences in phrasing of questions asked and the age ranges surveyed (for examples see NHS Digital 2019; Inchley et al. 2020; Brooks et al. 2020).

4.2 Physical Activity, Sleep and Digital Technology Use

Physical activity has many benefits for health not least in helping to prevent overweight and obesity and is widely thought to boost mental health and wellbeing. The current WHO guidelines recommend that young people get 60 min per day of moderate to vigorous physical activity (World Health Organization 2010). Over the last two decades a WHO initiative has been tracking population level physical activity on a global scale with the aim of improving levels of ‘sufficient’ physical activity. Against these targets, a recent report showed that the UK was falling well short of sufficient activity levels for adolescents, and importantly, there had been no improvement in the 20 years since the initiative began. It was found that only one in five young people took sufficient exercise on a daily basis, and gender inequalities were apparent too with just 15 % of girls versus 25 % of boys with sufficient activity levels (Guthold et al. 2020). In the Millennium Cohort Study, just under two out of five 14 year olds report engaging in moderate/vigorous activity on a daily basis, and boys are more likely to report doing so compared with girls (46.2 vs. 28.4 %—see Table 1). Examination of objective accelerometery data from a sub-sample of approximately 3500 MCS participants revealed that overall 40 % did 60 min or more of moderate to vigorous activity per day (Pearson et al. 2019).

Whilst there are no official UK Government guidelines on the amount of sleep adolescents should get, the importance of sleep for healthy development is becoming increasingly recognised. Sleep quantity and quality are thought to be influential across a range of developmental domains including BMI (Kelly et al. 2016b), mental health (Kelly et al. 2013a), and cognitive performance (Kelly et al. 2013b). About one in eight 14 year olds in the MCS reported short sleep duration (7 h or less per night, Table 1). A higher proportion reported having difficulties with disrupted sleep and this was more common for girls than boys (25.6 vs. 19.6 %).

The question of whether the use of digital technologies is causally linked to poor health (as already discussed in relation to mental health) is not clear cut. Sleep has been put forward as one of the potential pathways via which use of screens might impact on health (Kelly et al. 2018) and this has been recognised in a recent Chief Medical Officers’ report which includes guidelines on use of screens and getting enough sleep (Davies et al. 2019). Digital technology use is almost universal and many country settings, including the UK (Davies et al. 2019) endorse daily limits of around 2 h. These limits are exceeded by substantial proportions of young people, as detailed in Table 1, about two in five 14 year olds watch TV for 3 or more hours per day. Gaming is overall less prevalent but is heavily gendered, it is more common in boys than girls 45.5 vs. 12.0 %, whilst social media use is oppositely gendered, being more common among girls than boys, 46.2 vs. 24.1 % for 3 or more hours daily.

4.3 Intimate Partnered Relationships

Partnered intimate activity in adolescence is increasingly considered a normative part of development (Halpern 2010; Van de Bongardt et al. 2015). Much of the prior work on intimate activity in adolescence has had a narrow focus on the timing and circumstances of sexual debut, usually referring to first vaginal intercourse. Younger age at sexual debut correlates with unplanned teenage pregnancy and is associated negatively with sexually transmitted infections, mental health and educational attainment. Moreover, good sexual health in youth is associated with better sexual health and relationships throughout the lifecourse. In the UK, the legal age of consent is 16 and early sexual debut generally refers to having had sex prior to this age. In the UK there have been dramatic drops in teenage pregnancy rates over the last two decades from 43.9/1000 in 2000 to 16.8/1000 in 2018 (Office for National Statistics 2018). Alongside this, recent British prevalence estimates suggest that early sexual debut is becoming less common. For example, among young people born in the 1980s and 1990s, approximately 30 and 20 % respectively, report having had sex before age 16 (Mercer et al. 2013; Heron et al. 2015). Table 1 shows rates of partnered intimate activities among MCS participants aged 14. Activities are grouped into three categories: ‘light’ (handholding, kissing and cuddling); ‘moderate’ (touching and fondling under clothes); and ‘heavy’ (oral sex and sexual intercourse) (Mawditt et al. 2019). The majority of 14 year olds report some sort of partnered intimacy and only about one in thirty report having had intercourse/oral sex (Table 1).

4.4 Gambling and Violence

Gambling is increasingly recognised as a public health challenge in the UK, with problem gambling often going hand-in-hand with mental health problems and substance misuse. Commercial harms to health are clearly relevant here, with gambling companies spending billions of pounds marketing and advertising their products, targeting children and young people (Clark et al. 2020). It is estimated that some 55,000 adolescents (aged 11–16) are problem gamblers and about twice this number are at risk of becoming problem gamblers (Gambling Commission 2019). In an attempt to treat the complex health problems co-occurring with problem gambling, in 2019 the UK NHS announced the launch of gambling addiction clinics for 13–25 year olds. There is an important lifecourse dimension to gambling behaviours, and current estimates suggest that in the UK there are 300,000 adult problem gamblers with a further 1.7 million at risk (Conolly et al. 2018). Government policy on age restrictions vary depending on the type of gambling, for example, age 16 for the National Lottery, and age 18 for online betting and casinos as well as high street gambling outlets, whilst there are no age restrictions on the use of low stakes slot machines, and gambling products with virtual currency are freely available (Wardle 2018). In 14 year olds from the MCS about one in eight reported some form of gambling in the prior month (Table 1), and this was markedly more common for boys compared with girls. These figures are similar to other UK studies, for example the Gambling Commission’s annual survey reveals similar proportions of 11–16 year olds reporting gambling, including on slot machines and private bets (Gambling Commission 2019).

Youth violence has implications for mental health, substance use, social relationships, educational engagement and interactions with the criminal justice system. Paralleling wide ranging cuts, over the last decade, in youth services, and the removal of financial assistance for young people from economically disadvantaged families to stay in education, rates of youth violence have increased markedly (Marmot et al. 2020). About one third of 14 year olds from the MCS reported getting into physical fights and this was twice as common for boys than girls (41.4 vs. 21.3 %, Table 1), as was carrying a weapon (boys 3.7 vs. girls 1.9 %) on the other hand, street gang membership, although relatively rare being reported by one in twenty five, was slightly more common among girls than boys (4.5 vs. 3.5 %).

5 Conclusion

Over the last two decades there have been substantial changes in adolescent health in the UK. Overweight and obesity and poor mental health have become more common, and socioeconomic inequalities have widened. Conversely, there have been dramatic falls in the uptake of potential health damaging behaviours such as drinking and smoking, and declining rates of teenage pregnancy. Globally, technological changes mean that our worlds are highly interconnected and online communications are almost universal with young people typically spending several hours per day engaging in activities via social media and gaming platforms. The social determinants of health are increasingly acknowledged as important influences in young people’s lives, and the potential for commercial harms are unprecedented. Historically, UK public health policy has tended to concentrate on ‘downstream’ factors such as behaviours of young people themselves and their carers. Future policy developments aimed at improving health will require high level political buy-in to intervene on ‘upstream’ factors including commercial and broader social environments.