Australians are living longer but half of us have a chronic health condition which impacts our quality of life.

Key points: One in four Australians have two or more chronic illnesses

One in four Australians have two or more chronic illnesses Cancer, mental illness and coronary heart disease are the most common

Cancer, mental illness and coronary heart disease are the most common Chronic conditions account for 87 per cent of deaths

That is one of the key findings of the latest Australian Institute of Health and Welfare Australia's (AIHW) Health 2018 report.

The chair of the Chronic Disease Prevention Alliance, Professor Sanchia Aranda, said a significant proportion of conditions were caused by high body mass, poor diet and physical inactivity.

"As our Australian population ages, the number of us living with chronic disease is expected to balloon," she said.

"For Australia to lead on the global stage, we need to show a commitment to addressing the way food is formulated, promoted and labelled and creating environments where the healthy choice in nutrition and physical activity is the easy and obvious choice."

One in two adult Australians have at least one of eight common chronic conditions: cancer, cardiovascular disease, mental health conditions, arthritis, back pain and problems, chronic obstructive pulmonary disease, asthma and diabetes.

Almost one in four Australians have two or more of these conditions.

Do you know more about this story? Email Specialist.Team@abc.net.au

Dr Terry Slevin from Public Health Australia said a third of chronic diseases were preventable.

"We don't have a clear coherent plan to tackle this and we need to focus on prevention," he said.

The report found that as a whole, chronic conditions account for 87 per cent of deaths, 61 per cent of total disease burden and more than one-third of hospitalisations.

Obesity continues to be a major risk factor for chronic diseases.

The report found six out of 10 adults were now overweight or obese, while the proportion who are "severely obese" has doubled.

AIHW chief executive officer Barry Sandison said those with lower incomes were three times as likely to smoke or have diabetes.

"Those in the lowest group are more than twice as likely to avoid seeing a dentist or filling a prescription due to cost," he said.

What are we sick with?

As well as cancer, mental illness and coronary heart disease: