Young Australians are becoming more depressed, anxious and overweight, a report to be launched in Canberra today says.
The report finds the health and wellbeing of young Australians has deteriorated over the past 20 years, contesting the view their health is better than that of previous generations.
It finds mental disorders are the biggest contributors.
The report's author and founding director of think-tank Australia 21, Richard Eckersley, said the slide could harm the nation's future population health unless policy-makers changed their approach to health.
Mr Eckersley, who is also a visiting fellow at the ANU's National Centre for Epidemiology and Population Health, said orthodox views about youth health and wellbeing had tended to underestimate the growing importance of non-fatal chronic illness, especially mental disorders.
''I said 20 years ago that we weren't really getting to the crux of these issues that are affecting young people and their lives.
''And 20 years later I think that is still true.
''I acknowledged there have been important gains, like turning around the youth suicide rate, which was rising rapidly 20 years ago likewise with drug overdose deaths.
''When you look at the evidence now, it suggests that, despite those turnarounds in mortality, the underlying emotional and social wellbeing of young people has continued to decline.''
The report has found that the health and wellbeing of people 25 years and under has been declining across a range of measures.
Some physical illnesses linked to rising levels of obesity, notably diabetes, had increased with succeeding generations.
But the biggest impact on young people's health and wellbeing was mental disorder, ranked well ahead of the next most significant contributor injuries at 18 per cent.
Mental disorders accounted for almost half the burden of disease in the young population measured by both death and disability.
Amy Banson, 25, was named Young Canberra Citizen of the Year last April for raising awareness of mental health issues among young people.
Last year Ms Banson walked from Perth to Canberra to promote a program called Strength to Speak, which teaches young people how to lessen the risk of depression and anxiety in their lives.
Ms Banson said she thought the biggest threat to young people's health and wellbeing was their lack of understanding of measures that could prevent mental illness.
''Young people rate depression and anxiety as a pretty big barrier facing them today,'' she said.
She will speak at the official launch of the report tonight.
Mr Eckersley called yesterday for measures that went ''beyond things like shocking advertising campaigns [and] increased taxes on some alcoholic drinks''.
The report will be launched at 5pm at the John Curtin School of Medical Research before Mr Eckersley gives a public lecture, beginning at 6pm.
The report can be viewed at australia21.org.au