Is there anything I can do now to reduce my dementia risk?

Yes — and the evidence has strengthened substantially in recent years. The Lancet Commission on Dementia Prevention identified 12 modifiable risk factors that together account for up to 45% of dementia cases: hearing loss, physical inactivity, smoking, alcohol use, hypertension, obesity, depression, traumatic brain injury, air pollution, social isolation, diabetes, and low education level. In mid-life, the most actionable targets are treating hearing loss early (evidence is particularly strong for this), managing blood pressure, staying physically active, limiting alcohol, and addressing depression if present. None of these require specialist referral to start — a general practice review covers most of them.

Why has dementia overtaken heart disease as the leading cause of death?

Several things are happening simultaneously. Cardiovascular medicine has improved dramatically over the past two decades — more people are surviving heart attacks and living with well-managed heart disease than dying from it. Meanwhile, dementia incidence increases steeply with age, and the Australian population is ageing. These two trends together pushed dementia to the top of the mortality table. It is not necessarily that dementia has become more common at the individual level — it is partly that Australians are surviving long enough to reach the ages where dementia becomes a leading cause of death, while cardiovascular mortality has declined.

Dementia is now Australia's leading cause of death

What just happened

The Australian Institute of Health and Welfare released Australia’s Health 2026 on 9 July — the 20th edition of the biennial national health report. Three findings are standing out.

First, dementia has become Australia’s leading cause of death for the first time on record, overtaking ischaemic heart disease. Deaths from dementia increased 39% between 2015 and 2024. Second, 61% of Australians — approximately 15.4 million people — now live with at least one chronic condition. Third, 39% of young Australians aged 16 to 24 experienced a mental health condition in 2022, compared with 26% in 2007.

Alongside those figures: Australians are living longer than ever — average life expectancy now sits at 85.1 years for women and 81.1 years for men. Health system expenditure reached $270.5 billion in 2023–24.

The numbers tell two stories that need to be held at the same time.

The both-and

Dementia’s ascent is partly a success story

Dementia overtaking heart disease as Australia’s leading cause of death is, counterintuitively, partly evidence of how far cardiovascular medicine has come. More Australians are surviving heart attacks and living well-managed lives with heart disease than dying from it acutely. That is a genuine medical achievement, funded by decades of cardiovascular research, improved medications, stent technology, and lifestyle intervention.

The population that survived those events has aged. The older the population, the more dementia dominates the mortality picture. This shift has been observed and predicted for years across comparable countries.

But dementia’s rise is not entirely explained by cardiovascular improvement. The Lancet Commission on Dementia Prevention has identified up to 12 modifiable risk factors that together may account for 45% of dementia cases. Those factors — hearing loss, physical inactivity, hypertension, obesity, diabetes, depression, smoking, alcohol, traumatic brain injury, air pollution, social isolation, and low education level — are not evenly distributed. They cluster in particular socioeconomic and geographic groups. Rural and remote Australians, First Nations communities, and people in lower socioeconomic circumstances carry a disproportionate share of those risk factors and have less access to early intervention.

The “leading cause of death” headline is a national average that obscures enormous inequality in who is actually at risk.

Longer lives, but more years in poor health

The increase in life expectancy is real and should be acknowledged. A woman born in Australia today can expect to live to approximately 85. That is a meaningful shift from any previous generation.

What the data also shows is that those additional years are increasingly spent managing illness rather than living in full function. The ratio of healthy life years to total life years is not improving at the same rate as longevity itself. Australians are living longer with more chronic conditions, more complex medication regimens, and more years requiring some level of care.

This is the tension at the heart of modern healthcare. A system designed to keep people alive has largely succeeded. A system designed to keep people well into old age is still being built.

For the 61% of Australians with at least one chronic condition, that building is slow and uneven. Waiting times, GP shortages, fragmented specialist pathways, and a Medicare structure still oriented toward episodic acute care create a mismatch between what the population actually needs and what the system is set up to deliver.

Young people and mental health

The mental health finding is the one that deserves its own paragraph.

39% of young Australians aged 16 to 24 experienced a mental health condition in 2022. That figure was 26% in 2007. This is not a change in diagnostic criteria or measurement methodology — the survey instruments have been largely consistent. Something is actually shifting in the mental health of a rising generation.

What that something is remains contested: social media exposure, economic insecurity, pandemic effects, climate anxiety, and housing stress have all been nominated. The evidence implicates multiple factors. What is clearer is that the system response — youth mental health services, GP access, Medicare Better Access rebates — has not kept pace with the increase. Waitlists for clinical psychology through Medicare can stretch to months. Not all GP practices have integrated mental health care readily accessible.

The 39% figure is not a cause for alarm in the sense of “one in three young people is severely unwell.” Mental health conditions on this measure include anxiety disorders and mild depression that are genuinely manageable with good support. The alarm is in the gap between need and available support.

2 cents

The dementia finding is the one to sit with this week — specifically the prevention angle.

Up to 45% of dementia risk may be modifiable. That is an unusual figure in chronic disease medicine, where the modifiable fraction is often much smaller. It means that for a substantial portion of dementia, something could have been done earlier to change the trajectory.

The mid-life risk factors — hearing loss, hypertension, physical inactivity, and depression — are things general practice is placed to address. A general practice cardiovascular risk review covers most of them. Treating hearing loss is perhaps the single highest-leverage intervention in the evidence base; the effect size for hearing aid use on dementia risk has consistently surprised researchers.

For someone in their 40s who reads this data and feels a vague sense of “I should do something about this” — that instinct is correct. The question is which specific risk factor is most relevant to you. That is a fifteen-minute conversation with a GP, not a specialist referral.

For anyone watching a parent or grandparent with dementia: the AIHW report confirms what you are already living. The system has gotten better at diagnosing it; it is catching up on supporting the people inside it.

Verdict: yes — the most significant Australian health data release of the year, with genuine prevention implications for people in mid-life.

Sources cited

The Conversation — Mental illness is up in young people, dementia is now the biggest killer — Australia’s health in 2026 (9 July 2026). https://theconversation.com/mental-illness-is-up-in-young-people-dementia-is-now-the-biggest-killer-australias-health-in-2026-286946
The Conversation — Australians live longer than previous decades but spend more years in poorer health (9 July 2026). https://theconversation.com/australians-live-longer-than-previous-decades-but-spend-more-years-in-poorer-health-286649
AIHW — Australia’s Health 2026. https://www.aihw.gov.au/reports/australias-health/australias-health-2026