Australia’s housing crunch is no longer just an economic issue. Research clearly shows people who face housing insecurity are more likely to experience mental ill-health.

For this reason, secure housing must sit at the heart of any mental health plan.

Australia’s housing shortfall

Rents rose so fast in 2024 that Australia’s Rental Affordability Index now labels all major cities and regional areas “critically unaffordable” for people relying on benefits such as JobSeeker or a pension.

Vacancy rates hover near 1%, the lowest in decades. Mortgage costs chew the biggest slice of income since the mid-1980s.

On Census night in 2021, 122,494 Australians were homeless. Of these, more than 7,600 people slept rough, and nearly one-quarter were aged 12–24.

Data from homelessness services and headcounts of rough sleepers since 2021 suggest today’s figure is higher.

Housing stress quickly turns into mental distress

In a national survey, four in five renters said they spend more than 30% of their income on housing.

This 30% threshold is important. A 2025 study that followed more than 10,000 Australian renters found mental health drops fast once housing costs exceed the 30% mark. Missing a rental payment was linked to a further drop in mental health.

Earlier research has similarly found that among low- to moderate-income households, when housing costs exceed 30% of income, mental-health scores fall compared with similar households who spend less than 30%.

Another recent Australian survey found 38% of private renters feel their housing circumstances harm their mental health, versus 23% of owner-occupiers. This is driven by a mix of housing insecurity (such as short leases and eviction risk) and poor housing conditions (for example, cold homes or mould).

Meanwhile, helplines have reported cost-of-living pressures, including housing insecurity and homelessness, are driving an increasing number of calls.

Who is at highest risk?

In a sense, the housing ladder doubles as a mental health ladder.

Homeowners, with long-term security, sit on the top rung.

Private renters arguably ride the roughest road. Six-month leases, “no-grounds” evictions and “rent bidding” (where applicants may feel compelled to offer above the advertised rent to beat other applicants) keep people on edge.

Social housing residents often start with bigger challenges (43% live with mental health issues), but low rent and fixed leases steady the ship.

People with no stable home face the steepest climb. One review looking at people experiencing homelessness in high-income countries found 76% had a current mental illness.

This is likely linked in a large part to a feeling psychologists call “learned helplessness”. After the tenth rejected rental application – or the 15th, or the 20th – people ask “why keep trying?”. Motivation drops, and depression rises.

What’s more, a stable home makes it easier to do things like hold down a job or finish TAFE. Housing insecurity can therefore compound other problems such as unemployment, which are also linked to poor mental health.

What can we do about it?

Mental ill-health already drains roughly A$220 billion from Australia’s economy each year in lost productivity and health-care costs.

Housing stress piles extra costs onto the health-care system: more GP visits, more ambulance call-outs, more pressure on emergency departments.

Meanwhile, homeless shelters turn people away daily because beds are full.

This is without even accounting for the physical health effects of poor quality housing, including illnesses caused or exacerbated by problems such as mould, damp and cold.

All this means fixing the housing crisis is likely to generate savings for the health-care budget.

There are several ways we can do this.

1. Build more social housing

As of June 2024, about 4% of Australian households lived in social housing, equating to roughly 452,000 dwellings nationwide.

The National Housing Supply and Affordability Council’s State of the Housing System 2025 report recommends boosting social housing to 6%, with a long-term target of 10% of all homes. This would be a major step to cool the market and cut mental distress.

2. Protect renters

This should include ending no-grounds evictions, capping rent hikes to wage growth, and lifting Commonwealth Rent Assistance.

3. Link housing to health policy

On this point, Australia can take lessons from abroad. Finland, for example, has made “Housing First” national policy. This approach gives people experiencing long-term homelessness a permanent apartment and access to support. It has cut rough sleeping significantly.

Meanwhile, Aotearoa New Zealand’s Homelessness Action Plan aims to make homelessness “rare, brief and non-recurring” by funding Housing First in every region.

A trial in Canada gave more than 2,000 participants across several cities experiencing homelessness and mental illness a permanent home plus access to voluntary support.

Evidence from Canada shows Housing First keeps people housed and reduces demand on emergency and hospital services. Pilots in the United Kingdom are indicating similar benefits.

While there have been some promising programs in parts of Australia, there’s more to do.

Secure housing targets should sit inside the National Mental Health and Suicide Prevention Agreement. On the flip side, Australia is currently drafting a National Housing and Homelessness Plan. Mental health goals should be incorporated into that plan.

Just as clean water prevents disease and seat belts cut road deaths, a stable, affordable home is vital for mental health. Without bold action, we face a long-term social crisis.

This article is part of a series, Healthy Homes.

Ehsan Noroozinejad, Senior Researcher and Sustainable Future Lead, Urban Transformations Research Centre, Western Sydney University; Greg Morrison, Professor, Director of the Urban Transformations Research Centre, Lang Walker Endowed Chair in Urban Transformation, Western Sydney University, and Shameran Slewa-Younan, Associate Professor in Mental Health, Western Sydney University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

A doctor’s visit often ends with you leaving with a pathology request form in hand. The request form soon has you filling a sample pot, having blood drawn, or perhaps even a tissue biopsy taken.

After that, your sample goes to a clinical pathology lab to be analysed, in whichever manner the doctor requested. All this is done with the goal of getting to the bottom of the health issue you’re experiencing.

But after all the tests are done, what happens with the leftover sample? In most cases, leftover samples go in the waste bin, destined for incineration. Sometimes though, they may be used again for other purposes, including research.

Who can use my leftover samples?

The samples we’re talking about here cover the range of samples clinical labs receive in the normal course of their testing work. These include blood and its various components (including plasma and serum), urine, faeces, joint and spinal fluids, swabs (such as from the nose or a wound), and tissue samples from biopsies, among others.

Clinical pathology labs often use leftover samples to practise or check their testing methods and help ensure test accuracy. This type of use is a vital part of the quality assurance processes labs need to perform, and is not considered research.

Leftover samples can also be used by researchers from a range of agencies such as universities, research institutes or private companies.

They may use leftover samples for research activities such as trying out new ideas or conducting small-scale studies (more on this later). Companies that develop new or improved medical diagnostic tests can also use leftover samples to assess the efficacy of their test, generating data needed for regulatory approval.

What about informed consent?

If you’ve ever participated in a medical research project such as a clinical trial, you may be familiar with the concept of informed consent. In this process, you have the opportunity to learn about the study and what your participation involves, before you decide whether or not to participate.

So you may be surprised to learn using leftover samples for research purposes without your consent is permitted in most parts of Australia, and elsewhere. However, it’s only allowed under certain conditions.

In Australia, the National Health and Medical Research Council (NHMRC) offers guidance around the use of leftover pathology samples.

One of the conditions for using leftover samples without consent for research is that they were received and retained by an accredited pathology service. This helps ensure the samples were collected safely and properly, for a legitimate clinical reason, and that no additional burdens or risk of harm to the person who provided the sample will be created with their further use.

Another condition is anonymity: the leftover samples must be deidentified, and not easily able to be reidentified. This means they can only be used in research if the identity of the donor is not needed.

The decision to allow a particular research project to use leftover pathology samples is made by an independent human research ethics committee which includes consumers and independent experts. The committee evaluates the project and weighs up the risks and potential benefits before permitting an exemption to the need for informed consent.

Similar frameworks exist in the United States, the United Kingdom, India and elsewhere.

What research might be done on my leftover samples?

You might wonder how useful leftover samples are, particularly when they’re not linked to a person and their medical history. But these samples can still be a valuable resource, particularly for early-stage “discovery” research.

Research using leftover samples has helped our understanding of antibiotic resistance in a bacterium that causes stomach ulcers, Helicobacter pylori. It has helped us understand how malaria parasites, Plasmodium falciparum, damage red blood cells.

Leftover samples are also helping researchers identify better, less invasive ways to detect chronic diseases such as pulmonary fibrosis. And they’re allowing scientists to assess the prevalence of a variant in haemoglobin that can interfere with widely used diagnostic blood tests.

All of this can be done without your permission. The kinds of tests researchers do on leftover samples will not harm the person they were taken from in any way. However, using what would otherwise be discarded allows researchers to test a new method or treatment and avoid burdening people with providing fresh samples specifically for the research.

When considering questions of ethics, it could be argued not using these samples to derive maximum benefit is in fact unethical, because their potential is wasted. Using leftover samples also minimises the cost of preliminary studies, which are often funded by taxpayers.

Inconsistencies in policy

Despite NHMRC guidance, certain states and territories have their own legislation and guidelines which differ in important ways. For instance, in New South Wales, only pathology services may use leftover specimens for certain types of internal work. In all other cases consent must be obtained.

Ethical standards and their application in research are not static, and they evolve over time. As medical research continues to advance, so too will the frameworks that govern the use of leftover samples. Nonetheless, developing a nationally consistent approach on this issue would be ideal.

Striking a balance between ensuring ethical integrity and fostering scientific discovery is essential. With ongoing dialogue and oversight, leftover pathology samples will continue to play a crucial role in driving innovation and advances in health care, while respecting the privacy and rights of individuals.

Christine Carson, Senior Research Fellow, School of Medicine, The University of Western Australia and Nikolajs Zeps, Professor, School of Public Health and Preventive Medicine, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.