Poverty is usually thought of as a lack of money, but it also equates, tragically, to a lack of time. Wealthier Australians not only live better than the less privileged among us, but also longer.

Six years. That is now the average gap in life expectancy between the bottom 20 per cent of the population and the top 20 per cent, according to a new study of health inequality in Australia.

For people in the lowest 10 per cent of the population, it is 10 years. Indeed, the gap seems to be widening across the board, according to Professor Philip Clarke of the Melbourne School of Population and Global Health at the University of Melbourne, one of the authors of the soon-to-be published study.

This is not apparent in the official data. Only this week, new figures from the Australian Bureau of Statistics boasted “record highs” for Australian life expectancy. A child born today can expect to live to nearly 83, on average.

But averages do not tell the full story. Gains to our overall life expectancy, which has steadily increased for more than a century, have slowed appreciably, and have, over the past couple of years, declined in some areas.

It is not yet going backwards in this country, as is the case in the United States. There, mortality rates for a group largely comprising white, working-class, middle-aged people of limited education have increased so dramatically as to skew the average life expectancy of the entire nation. These have been tagged “deaths of despair” by researchers, and are caused by substance abuse-related lifestyle diseases and suicide. They are the downwardly mobile victims of globalisation and neoliberal economics.

In Australia? Well, it’s hard to tell because of the paucity of data. The preconditions are evident already – flat wages, a decline in the availability of low-skill jobs, declining social services driven by government austerity, increasing rates of long-term unemployment and substance abuse, suicide and lifestyle diseases among the middle-aged, particularly men. It sounds a warning.

As does Clarke’s research with co-writer Guido Erreygers, “Defining and measuring health poverty”, which seeks to establish a health poverty line, analogous to that which exists already for economic poverty.

Using Australia’s best longitudinal dataset, the Household, Income and Labour Dynamics (HILDA) survey, and complex statistical methods, the pair made a bold attempt at the task – going back 15 years to look at the correlation between the income and health of 24,820 individuals.

What they found was alarming. Among people in the bottom 40 per cent of the population – as measured by income – life expectancy-related health poverty rates have not improved.

“Moreover, this gap is widening over time,” they write, “with much of the rise occurring after 2009.”

The increase was dramatic, with the gap between top and bottom widening by about 50 per cent, as life expectancy improved for wealthier Australians.

“The bottom line is the rich live six years longer than the poor,” says Andrew Leigh. “And that, in my view, is a massive issue.”

Australia has long prided itself on steady increases to life expectancy, but in fact the six-year gap was first identified several years ago by Clarke and Labor MP Andrew Leigh, then an economics professor at the Australian National University.

It’s certainly no surprise to John Glover, director of the Public Health Information Development Unit at Torrens University. He cites statistics comparing the rates of premature deaths – those who die before age 75 – over a quarter-century to make the point. In each five-year period from 1987-91 to 2011-15, the gap between rich and poor grew.

“The good news is that over that period, premature mortality declined sharply by around 40 per cent. But it did not decline equally,” he says.

Glover says in the late ’80s men in the most disadvantaged quintile of the population were 60 per cent more likely to die prematurely. “By the end [2011-2015] it was almost double,” he says.

Over the same period, the “inequality ratio” also rose for women, with those in this low-income group 82 per cent more likely to die prematurely by 2015.

There has always been a gap in the relative health of people of different means, of course. In the case of Indigenous Australians, this differential – currently between eight and nine years – has been widely recognised and subject to government action directed to “closing the gap”.

“The suggestion is that everything’s good in Australia, that we’re doing very well on life expectancy, apart from Aboriginal people,” says Glover. “But there are other gaps as well, other disadvantaged [groups].

“It’s very hard to pull out data on these other groups … people who are unskilled or older people who have lost their jobs. It’s very crude – what you get is that the person died, and this is where they last lived.”

In the US, they have better data, which Princeton University academics Anne Case and Sir Angus Deaton pulled together in 2015 for a landmark paper: “Rising morbidity and mortality in midlife among white non-Hispanic Americans in the 21st century.”

Deaton won a Nobel prize in economics that year for his work on consumption, poverty and welfare, and Case coined the term “deaths of despair”. They found the rates of chronic health problems and death among this group had been rising since at least the turn of the century.

They found mortality rates continued to climb through 2015. “Additional increases in drug overdoses, suicides, and alcohol-related liver mortality – particularly among those with a high school degree or less – are responsible for an overall increase in all-cause mortality among whites,” they wrote.

Deaton and Case hypothesised the cause was “cumulative disadvantage” over decades, “in the labor market, in marriage and child outcomes, and in health”.

The pair will expand on the subject in a book, due out early next year. Its title: Deaths of Despair and the Future of Capitalism.

It’s a similar story in Britain, where health poverty has risen and life expectancy has decreased during the past decade or so since the global financial crisis.

But, in truth, blame cannot be laid wholly on one side of politics. The problem has grown under both the Democrats and Republicans in America, Labour and the Tories in Britain and Labor and the Coalition in this country.

As Glover notes, the mortality gap began widening in this country several decades ago, “around the time the Australian economy was opened up, the world economy was opened up. Then a whole lot of things changed. This globalisation is the only explanation I can think of.”

In Australia, the average age of a person on Newstart is now 45. The fastest-growing cohort of people on unemployment benefits is over 55, and they stay on benefits, on average for almost four years. The Morrison government, in its refusal to increase Newstart to a level above the poverty line, suggests the unemployed are young and work-shy. They are not.

Meanwhile, a comprehensive review of Australians’ health last year by the Australian Institute of Health and Welfare (AIHW) showed a worrying long-term upward trend in substance abuse by people in middle age.

Between 2001 and 2016, illicit drug abuse jumped among people in their 40s – from 12 to 16 per cent – and almost doubled, to 12 per cent, among those in their 50s, even as it declined in other age groups.

We lack data relating to the education or class of these people, or a definite link between joblessness and substance abuse, but the correlation is strongly suggestive.

Other statistics in the AIHW data also indicate deaths of despair are occurring in Australia.

In 1997, 3.5 out of every 100,000 men in their 40s died from what the institute categorises as accidental poisonings, including drug overdoses. Two decades later, that had grown to 18 men per 100,000.

Suicide rates also have increased significantly among both men and women in their 40s and 50s. The median age of suicide is now 44, and it accounts for the highest number of years of potential life lost among all causes of death.

Health inequality is not manifested in only deaths of despair, though, says Andrew Leigh. But this can only be seen when you have detailed data.

“One of the starkest findings I’ve come across looked at the number of teeth that people have. The rich have seven more teeth than the poor,” says Leigh.

“Think about that. You’re not going to get a good customer service job if people flinch when you smile. It has huge implications for the marriage markets and for social life more broadly.”

And poor oral health, medical research shows, is related to other health problems, including addiction.

“One of the chief reasons people start using alcohol and drugs is to dull the pain of sore teeth,” says Leigh.

The evidence of health poverty and its relationship to economic poverty is abundant – in rates of smoking and obesity, and various lifestyle diseases.

To blame the health-poor for their poverty – they shouldn’t smoke and drink so much, should just say no to drugs of dependence, should exercise more et cetera – ignores the causal factors. People who become obese because they eat bad food often can’t afford fresh meat and produce. They can’t get dental treatment on Medicare, but they can get painkillers. Long commutes rob them of time to exercise. And so on.

“When you talk about behaviours,” says Stephen Duckett, health program director at the Grattan Institute, “you’ve also got to think about why those behaviours exist.

“Why do low-income people smoke more than high-income people? It’s not simply that high-income people know the risks of smoking. It’s also that high-income people have got less stressful lives.

“Just focusing on behaviour individualises the problem and deflects attention away from the systemic factors that are at play.”

In this country, decision-makers on the whole have not focused much on the issue of health inequality and its fatal consequences.

“The bottom line,” says Leigh, “is the rich live six years longer than the poor. And that, in my view, is a massive issue.

“How much would most of us be willing to give up to have one more year of healthy life, let alone six of them?”

It’s a good question. Would we, as a nation, be prepared to give up on an economic model that has deemed a whole cohort of people surplus to requirements?

Because the evidence suggests that’s what it would take.