Mental health disorders affect about 1 in 7 or roughly 13 percent of all Australian teenagers. That’s similar to the rate of mental health disorders in children, but what changes in the transition from childhood to adolescence is the nature of those disorders.

In childhood, common mental health conditions include attention deficit hyperactivity disorder, oppositional defiant disorder and certain forms of anxiety. In adolescence, those disorders give way to depression, other forms of anxiety, and self-harm. Uncommon but severe problems such as schizophrenia, bipolar disorder and anorexia nervosa also typically begin in adolescence.

Just like physical disorders, mental health disorders can be mild, moderate or severe. If a teenager has mild problems, it means their distress is minor and they can still function normally although it may take substantial and unusual effort. Two to three percent of teenagers experience more severe difficulties. For these teenagers, symptoms are distressing and their capacity to carry out most daily activities is seriously disrupted.

Depression is particularly common among teenagers, and can be very damaging. It’s often misread as a behavioural problem because of the irritability and apathy it can produce. Some depressed teenagers attempt to modify their symptoms with alcohol, marijuana, or other drugs. In others, the only obvious indication is a sudden and unexplained decline in school performance.

While only some teenagers are affected by mental health disorders, all teenagers are faced with things that challenge their mental wellbeing. In 2018, an Australian survey of young people aged 15 to 19 years found the top three things causing them concern were coping with stress, school or study problems, and body image. 

Lifestyle choices like prioritising sleep, keeping physically active, eating well and limiting alcohol and caffeine intake can help support mental wellbeing in teenagers, and help them recover from mild mental health difficulties.

• Typically, serious mental health disorders such as schizophrenia, bipolar disorder and anorexia nervosa first emerge in adolescence. Identifying those issues early and giving teenagers the support and treatment they need can have a positive impact on the progress of those disorders into adulthood.
• The symptoms and side effects of depression, including apathy, irritability and alcohol and drug use, can be misread as ‘typical’ teenage moodiness. Teachers, health professionals and parents, in particular, are not good at identifying depression in teenagers, and so the problem often goes undetected. Identifying and supporting a teenager with depression can prevent a mild mental health issue from developing into a serious disorder.
• Most mental health problems in the Teenage Decade are either mild and transient (the equivalent of a cold) or mild and recurrent (the equivalent of mild asthma). Teenagers with mild mental health problems can usually continue to function normally, although it may take substantial and unusual effort. For those teenagers, the best approach is to be supportive, and to adopt a ‘watch-and-wait’ attitude to see if the problem resolves by itself.
• Two to three percent of teenagers experience more severe difficulties characterised by distressing symptoms and substantial disruption to their daily activities. These teenagers need the support of specialist services.