The period between birth and becoming an adult is a turbulent one. In this phase of life, young people experience a series of rapid and strong changes The habits that affect well-being and health also correspondingly change. Children eat a relatively healthy diet and exercise regularly, which is increasingly rarely the case among adolescents and young adults. Topics like alcohol, tobacco and drugs such as cannabis become relevant during teenage years. As the behavioural patterns practised during adolescence have a particularly strong impact on subsequent behaviour as an adult, preventative and health programmes must take young people’s attitudes and knowledge into account if they are to be truly effective.