Indigenous Australians are more than twice as likely to die before their fifth birthday than non-Indigenous Australians.

Australia's Health 2018, a report released by the Australian Institute of Health and Welfare on Wednesday, says indigenous Australians have a shorter life expectancy than non-indigenous Australians and are at least twice as likely to rate their health as fair or poor.

On average, indigenous Australians have lower levels of education, employment and income and poorer quality housing than non-indigenous Australians.

However there have been improvements in child mortality rates, smoking rates and drinking rates for those over the age of 15.

Factors in the health gap include higher rates of smoking and risky alcohol consumption, less exercise, a greater risk of high blood pressure and difficulty accessing affordable health services.

The report states that if indigenous adults were to have the same household income, employment rates, hours worked and smoking rate as non-indigenous Australians, the health gap would be reduced by more than a third.

Levels of health vary within the indigenous population, with those employed in 2014-15 less likely to smoke and use illicit substances and more likely to have an adequate daily fruit intake.

IMPROVEMENTS IN INDIGENOUS HEALTH

- Child mortality rates (zero to four) decreased from 217 deaths per 100,000 in 1998 to 140 deaths per 100,000 in 2016

- Between 2005-2007 and 2010-2012, the gap in life expectancy at birth between indigenous and non-indigenous Australians decreased from 11.4 to 10.6 years for males and 9.6 to 9.5 years for females

- Smoking rates declined from 51 per cent in 2002 to 42 per cent in 2014-15, concentrated in non-remote areas.

- In 2014-15, 17 per cent of indigenous Australians aged between 15-17 smoked, compared to 30 per cent in 1994

INDIGENOUS HEALTH COMPARED TO NON-INDIGENOUS HEALTH

- 2.1 times as likely to die before their fifth birthday

- 2.7 times as likely to experience high or very high levels of psychological distress

(Source: Australia's Health 2018, Australian Institute of Health and Welfare)