Modifiable risk factors for dementia (And what you can do about them)
Dementia is now Australia's leading cause of death, affecting an estimated 446,500 Australians in 2026. According to the 2024 Lancet Commission, up to 45% of dementia cases globally may be prevented or delayed by addressing 14 modifiable risk factors, including physical inactivity, depression, social isolation, hearing loss, and high blood pressure. Midlife is a critical window for action: the earlier protective habits are established, the greater the potential benefit across the life course.
The report emphasises that dementia risk builds across the lifespan — and so does cognitive and physical reserve. Cognitive reserve is your brain’s ability to adapt and cope with damage. Physical reserve helps you bounce back after stress, illness, or injury — and continue functioning well as you age. It’s never too early or too late to make lifestyle changes, such as:
Staying cognitively, physically, and social active
Managing your vascular health
Finding your tribe and building belonging
Staying curious and engaging in lifelong learning
Cultivating a sense of meaning and purpose in life — something we explore in more depth in our companion articles on how meaning shapes our health as we age, and why a sense of purpose can help support brain health over time.
In Australia, the stakes are particularly significant. In 2024, dementia overtook ischaemic heart disease to become the leading cause of death in Australia for the first time on record, and has been the leading cause of death among Australian women since 2016 (Australian Bureau of Statistics, 2025). There are currently an estimated 446,500 Australians living with dementia, with projections suggesting this will exceed one million by 2065 (AIHW, 2025). Despite this, a 2024 survey for Dementia Australia found that more than one in four Australians incorrectly believe there is nothing they can do to reduce their risk, yet nearly nine in ten said they would like more information about protecting their brain health (Dementia Australia, 2024)."
However, prevention isn’t just about information, it’s about change. Many of us already know what supports future brain health. So why can’t we get started or stick with it? Thought traps like “I’ll start tomorrow,” unhelpful patterns, self-doubt, apathy, and feeling overwhelmed by other commitments can get in the way.
What are cognitive reserve and physical reserve?
Cognitive reserve is the brain's ability to adapt, compensate, and continue functioning despite damage or age-related change. It is built over a lifetime through education, mentally stimulating work and hobbies, social engagement, and lifelong learning; and it appears to delay the onset of dementia symptoms even when underlying brain changes are present (Livingston et al., 2024).
Physical reserve refers to the body's capacity to maintain physical function and withstand the effects of ageing and disease across the lifespan. Physical reserve is built through regular exercise, healthy diet, and management of vascular risk factors, and is closely linked to brain health, because the vascular, metabolic, and inflammatory pathways that support heart health also support the brain (Livingston et al., 2024).
What are the key modifiable risk factors for dementia?
1. What is the link between education and dementia risk?
Missing out on education, complex work, or mentally stimulating activities reduces cognitive reserve — your brain’s ability to adapt and cope with damage.
What helps:
Mentally challenging activities — complex hobbies or work, reading, puzzles, writing letters or diaries, creative arts, higher education — especially in midlife
Staying curious and keeping on learning
Ask: “What am I a newbie at right now?”
2. How does depression increase dementia risk and what helps?
Depression, especially in midlife, is a known risk factor for dementia. It may also be an early symptom or a response to cognitive decline. Experiences such as ageism and feeling overlooked in midlife and later life can also contribute to depression, something we explore further in our article: When the World Stops Seeing You: Ageism, Depression, and the Hidden Toll of Being Overlooked in Midlife and Later Life.
What helps:
Talk to your GP about a Mental Health Treatment Plan
Engage with a clinical psychologist using evidence-based therapies
Regular physical exercise supports mood and brain health
3. Why does social isolation increase the risk of dementia?
Lacking meaningful, supportive relationships increases dementia risk, especially in older adults who live alone or feel disconnected.
What helps:
Build a diverse social network across all ages
Focus on quality over quantity in relationships
Join purpose-driven groups, clubs, or communities
Reconnect with supportive family and friends
4. How does physical activity protect against dementia?
Heart and brain health are closely linked. Inactivity lowers not only cognitive reserve, but also physical reserve, which is your body’s ability to recover and stay strong with age.
What helps:
Aim for 150+ minutes of moderate activity weekly
Mix cardio, strength, balance, and flexibility
Movement doesn’t have to be a formal activity; weave it into your daily routine
Choose activities that feel meaningful
5. How do vascular health conditions affect dementia risk?
These conditions are linked to poor vascular health, a key factor for dementia.
What helps:
Follow a Mediterranean-style diet (high fibre, omega-3s, whole grains, greens)
Maintain a healthy BMI (18–25)
See your GP for regular health checks
Combine lifestyle change with medical and psychological support
6. What is the relationship between alcohol use and dementia?
Alcohol damages brain structure and increases inflammation. Binge drinking in midlife is particularly harmful.
What helps:
Avoid binge drinking
Drink moderately — or not at all.
Choose alcohol-free days or ‘Dry July’
Understand your triggers for drinking
Consider therapy to shift unhelpful patterns of behaviour
7. Does smoking increase dementia risk?
Smoking damages blood vessels and increases inflammation, raising dementia risk.
What helps:
Quit smoking with support — especially as you approach midlife
Avoid second-hand smoke exposure
8. How does head injury contribute to dementia risk?
Traumatic brain injury (TBI) from hits or jolts to the head — especially moderate to severe or repeated injuries — increases dementia risk and contribute to earlier onset.
What helps:
Wear helmets during risky activities and contact sports
Avoid repeated head injuries
Seek medical care after a concussion
9. Can air pollution affect brain health and dementia risk?
Air pollution, especially fine particles, is linked to brain inflammation and cognitive decline.
What helps:
Avoid outdoor exercise in high-pollution areas
Stay indoors on days with poor air quality (urban smog or bushfire smoke)
Use air filters at home if needed
10. Why is untreated hearing loss a risk factor for dementia?
Hearing loss reduces brain stimulation and can lead to isolation and cognitive decline.
What helps:
Regular hearing checks from age 50
Address any shame or stigma about hearing aids
11. How does untreated vision loss affect cognitive health?
Poor vision, if uncorrected, contributes to cognitive decline through reduced sensory input and engagement.
What helps:
Have regular eye exams
Keep your glasses prescription up to date
Treat cataracts and age-related vision changes early
Lifestyle matters — how many protective factors do you have?
In a landmark 30-year UK study, people aged 45–59 who adopted four or more healthy habits reduced their risk of dementia by up to 60% (Elwood et al., 2013).
The protective habits included:
Daily physical activity — e.g., walking 3 km or cycling 15 km
A healthy, brain-friendly diet — low in saturated fat, with 3+ servings of fruit and veg daily
Maintaining a healthy BMI (between 18–25)
Reducing alcohol intake
Not smoking
While no lifestyle change guarantees prevention — because some links are only partly causal — the science is increasingly clear: healthy habits lower your risk of developing dementia. Recent studies indicate that means more years of good health, and less time in poor health if dementia does develop.
“Prevention approaches should aim to decrease risk factor levels early (the earlier, the better) and keep them low throughout life (the longer, the better)” — Livingston et al., 2024, p 572.
In Australia specifically, a 2023 study found that physical inactivity is the single largest modifiable risk factor for dementia, exceeding smoking, alcohol use, and traumatic brain injury in its population-level impact (Dementia Australia, 2023). This makes regular movement not just a general health recommendation, but a particularly urgent brain health priority for Australians in midlife and beyond.
Frequently asked questions
Q: What is a modifiable risk factor for dementia? A: A modifiable risk factor is a condition or behaviour that increases the likelihood of developing dementia and that can be changed or reduced through lifestyle choices or medical treatment. The 2024 Lancet Commission identified 14 modifiable risk factors including physical inactivity, depression, social isolation, hearing loss, high blood pressure, smoking, excessive alcohol use, obesity, diabetes, air pollution, head injury, low educational engagement, untreated vision loss, and high LDL cholesterol. Collectively, these account for approximately 45% of dementia cases worldwide (Livingston et al., 2024).
Q: How many dementia cases could be prevented in Australia? A: According to the 2024 Lancet Commission, up to 45% of dementia cases globally may be preventable or delayable through addressing modifiable risk factors. In Australia, national burden of disease data suggest that 43% of dementia burden is attributable to six key modifiable risk factors (tobacco use, overweight and obesity, physical inactivity, high blood pressure in midlife, high blood plasma glucose, and impaired kidney function) (AIHW, 2025).
Q: When is the best time to start reducing dementia risk? A: The Lancet Commission emphasises that dementia risk builds across the entire lifespan, and so does the protective benefit of healthy habits. Midlife (approximately ages 40–65) is considered a particularly critical window, because many risk factors such as high blood pressure, physical inactivity, excessive alcohol use, and depression have their greatest impact during this period. However, the Commission is clear that it is never too early or too late to act: "Prevention approaches should aim to decrease risk factor levels early; the earlier, the better, and keep them low throughout life" (Livingston et al., 2024, p. 572).
Q: What is the single most important lifestyle change for reducing dementia risk? A: No single change eliminates risk, but physical activity has among the strongest and most consistent evidence across the literature. In Australia, physical inactivity has been identified as the largest modifiable risk factor for dementia exceeding smoking, alcohol, and traumatic brain injury in population-level impact (Dementia Australia, 2023). The Lancet Commission recommends at least 150 minutes of moderate-intensity activity per week, combining cardiovascular exercise, strength training, and activities that reduce sedentary time.
Q: Does dementia run in families — and does that change what I should do? A: Having a family history of dementia or carrying certain genetic variants (such as APOE-e4) does increase risk. However, genetics explain only a portion of dementia cases, and the evidence is clear that modifiable lifestyle factors influence risk even in people with a genetic predisposition. The Lancet Commission's guidance applies regardless of family history: building cognitive and physical reserve across the lifespan remains the most evidence-supported approach to reducing risk (Livingston et al., 2024).
Q: Can psychological therapy help with dementia prevention? A: Psychological support can help address several of the modifiable risk factors most strongly linked to dementia, particularly depression, social isolation, and the behavioural patterns that make healthy habit change difficult (Livingston et al., 2024). Cognitive Behavioural Therapy (CBT) is an evidence-based, first-rank treatment for depression in older adults (González-Martín et al., 2023) and has strong support for addressing the mood and behavioural factors that contribute to dementia risk. Acceptance and Commitment Therapy (ACT) offers a complementary approach, supporting psychological flexibility and value-driven behaviour change, qualities that are particularly relevant when the challenge is not knowing what to do, but doing it consistently over time (Hayes et al., 2006; Arnold et al., 2022).
Ready to take action?
If you’re feeling stuck between knowing what supports brain health and actually doing it, we’re here to help you turn good intentions into action with tailored support that fits your everyday life.
Upside Stories offers online therapy and individualised 10-week programs like Healthy Brain, Happy Heart, designed for midlife and beyond.
Start by booking a free 20-minute consultation.
References & reading
Arnold, T., Haubrick, K. K., Klasko-Foster, L. B., Rogers, B. G., Barnett, A., Ramirez-Sanchez, N. A., & Gaudiano, B. A. (2022). Acceptance and commitment therapy informed behavioral health interventions delivered by non-mental health professionals: A systematic review. Journal of Contextual Behavioral Science, 24, 185–193. https://doi.org/10.1016/j.jcbs.2022.04.003
Australian Bureau of Statistics. (2025). Causes of death, Australia, 2024. Australian Government. https://www.abs.gov.au/statistics/health/causes-death/causes-death-australia/latest-release
Australian Institute of Health and Welfare. (2025). Dementia in Australia. Australian Government. https://www.aihw.gov.au/reports/dementia/dementia-in-aus
Dementia Australia. (2024). Dementia facts and figures. https://www.dementia.org.au/about-dementia/dementia-facts-and-figures
Dementia Australia. (2023). Physical inactivity and dementia risk in Australia [Media release]. https://www.dementia.org.au/media-centre/media-releases/make-brain-health-your-new-years-resolution-2025
Elwood, P., Galante, J., Pickering, J., Palmer, S., Bayer, A., Ben-Shlomo, Y., … Gallacher J. (2013). Healthy Lifestyles Reduce the Incidence of Chronic Diseases and Dementia: Evidence from the Caerphilly Cohort Study. PLoS ONE, 8(12), e81877. https://doi.org/10.1371/journal.pone.0081877
González-Martín, A. M., Aibar Almazán, A., Rivas Campo, Y., Rodríguez Sobrino, N., & Castellote Caballero, Y. (2023). Addressing depression in older adults with Alzheimer's through cognitive behavioral therapy: Systematic review and meta-analysis. Frontiers in Aging Neuroscience, 15, 1222197. https://doi.org/10.3389/fnagi.2023.1222197
Hayes, S. C., Luoma, J. B., Bond, F. W., Masuda, A., & Lillis, J. (2006). Acceptance and commitment therapy: Model, processes and outcomes. Behaviour Research and Therapy, 44(1), 1–25. https://doi.org/10.1016/j.brat.2005.06.006
Livingston, G. et al. (2024). Lancet Commission on Dementia Prevention, Intervention, and Care, 404(10452), 572–628. https://doi.org/10.1016/S0140-6736(24)01296-0
