Mental illnesses are also called mental disorders. They are extremely common in the Australian population.
1 in every 5 Australians — about 4 million people — suffers from a mental illness in a given year, and almost half the population has suffered a mental disorder at some time in their life. The most common mental disorders are depression, anxiety and substance use disorders.
There are many different types of mental illness. They can range from mild disorders lasting only a few weeks through to severe illnesses that can be life-long and cause serious disability.
Mental illnesses can affect people’s thoughts, mood, behaviour or the way they perceive the world around them. A mental illness causes distress and affects the person’s ability to function at work, in relationships or in everyday tasks.
Although mental illness is treatable, about two thirds of people with mental illnesses do not seek any treatment. Psychological therapy, medicine and lifestyle changes can be effective for mental illness. If you suspect that someone may have signs of a mental illness, the first step for them is to visit a doctor or health professional.
Last reviewed: November 2018