Worldwide, at least 13% of people between the ages of 10 and 19 live with a diagnosed mental-health disorder, according to the latest State of the World’s Children report, published in 2021 by the United Nations children’s charity UNICEF. It’s the first time in the organization’s history that this flagship report has tackled the challenges in and opportunities for preventing and treating mental-health problems among young people. More than 40% of young people's mental health illnesses are anxiety and depression (those aged 10–19). According to UNICEF, teen suicide is the fourth most common cause of death globally (after traffic accidents, TB, and interpersonal violence) (aged 15–19). Suicide is the second-leading cause of mortality for young people in that age group in western Europe and North America, as well as in eastern Europe and central Asia.

Sadly, psychological distress among young people seems to be rising. One study found that rates of depression among a nationally representative sample of US adolescents (aged 12 to 17) increased from 8.5% of young adults to 13.2% between 2005 and 20171. There’s also initial evidence that the coronavirus pandemic is exacerbating this trend in some countries. For example, in a nationwide study2 from Iceland, adolescents (aged 13–18) reported significantly more symptoms of mental ill health during the pandemic than did their peers before it. And girls were more likely to experience these symptoms than were boys. This is due to the role of rumination in the development of depression. According to the Nolen-Hoeksema study women are more likely to amplify depression by ruminating about their feelings and their possible causes - that is, they think a lot about how they feel and try to understand the reasons they feel the way they do. In one study, Nolen-Hoeksema (2000) found that both men and women who ruminate more following the loss of loved ones are more likely to become depressed and to suffer longer and more severe depression than those who ruminate less. According to the researcher, rumination appears to more consistently predict the onset of depression rather than the duration, but rumination in combination with negative cognitive styles can predict the duration of depressive symptoms.

Only one-third of funding for mental health research, according to UNICEF, is devoted to young people, despite the fact that the majority of mental health illnesses start during adolescence. In addition, the study is fragmented because the scientists involved frequently belong to specific fields like psychiatry, pediatrics, psychology, and epidemiology, and there are frequently weak connections between the research and healthcare services. This means that there are few proven preventative and therapeutic approaches, and there is a paucity of knowledge about what works, when, and why.

A class of medications known as selective serotonin repute inhibitors, which raise serotonin levels in the brain and are meant to improve emotion and mood, is the most widely used treatment for anxiety and depression in the entire world. This is based on the psychological serotonin hypothesis which states that lower levels of serotonin leads to a predisposition of depression. However, this hypothesis could be proved wrong as it had limited effectiveness and significant side effects have prompted research into additional physiological pathways that may play a role in adolescent depression and anxiety in order to create novel treatments. Contrarily, researchers have discovered that, in some cases, enhancing young people's cognitive and interpersonal abilities can be more successful in avoiding and treating anxiety and depression. However, the cause for this is unknown. For instance, according to Marc Bennett at the University of Cambridge in the UK and colleagues6, although the underlying neurobiological mechanisms are unknown, the practice of "decentring" or "psychological distancing" (encouraging a person to adopt an objective perspective on negative thoughts and feelings) can help both prevent and treat depression and anxiety.