Australian authorities say a new report shows a large proportion of negative health conditions are caused by substance abuse and poor mental states.

A report published this week in medical journal The Lancet surveyed the premature deaths and the years lived with disability for hundreds of diseases in 187 countries.

Australian health expert and contributor to the report Professor Harvey Whiteford from the University of Queensland says it shows mental health and substance use disorders are the prime causes of disability in the world, with depression alone accounting for 40 per cent of disability.

Researchers found opioid narcotics such as heroin caused the most illness, followed by amphetamines. Drug addiction is at its highest rate among men aged 20 to 29.

The findings of the report show that nearly a quarter of the health-related disability in Australia comes from mental health disorders and substance abuses, but these areas of health are woefully under-funded.

“The amount of funding we spend on services in Australia is nowhere near commensurate with the size of the burden,” Professor Whiteford said.

Details are available online for the report titled 'Global burden of disease attributable to mental and substance use disorders: findings from the Global Burden of Disease Study 2010'.