Dementia in Australia

There are several risk factors that can increase a person’s likelihood of developing dementia. Some risk factors can be avoided or reduced (known as ‘modifiable risk factors’) and others cannot be changed (known as ‘non-modifiable risk factors’). As there is currently no cure for dementia, minimising modifiable risks is currently the best way to prevent dementia (Livingston et al. 2024; Prince et al. 2014). 

Having one or more of these risks factors does not mean you will develop dementia, rather it increases the individual likelihood of dementia developing.

How can you reduce your risk?

It is never too early, and never too late, to take action to reduce the risk of dementia (Long 2023).

The World Health Organization has recommendations on actions that one can take to reduce risks associated with cognitive decline and dementia. These include cognitive, behavioural, social and pharmacological interventions aimed at improving health overall and reducing exposure to known modifiable risk factors associated with dementia (WHO 2023).

Multi-component interventions that target the following key risk factors have been proven to delay cognitive decline in international and Australian studies (FINGERS 2025, Brodaty et al. 2025). This means that people who completed these trials were less likely to develop dementia or were older when they developed dementia. The key risk factors and recommendations are:

Healthy food

Following a nutritious and varied diet reduces the likelihood of heart disease, stroke and type 2 diabetes, key risk factors for dementia (Livingston et al. 2024).

Cognitive decline was delayed in studies that included a Mediterranean diet which is high in unprocessed plant foods, like legumes, vegetables, fruits, nuts, seeds, with moderate amounts of fish and seafood and low amounts of meat, dairy and eggs (FINGERS 2025, Brodaty et al. 2025).

Physical activity

Regular exercise improves a person’s heart, blood vessels and brain (Livingston et al. 2024).

Physical activity includes regular cardiovascular exercise, strength training and limiting time spent sitting, as described in the Physical activity and exercise guidelines for all Australians. There is strong evidence that physical activity is protective against dementia, and it is most beneficial when both cardiovascular and strength training are included (FINGERS 2025).

Mental stimulation

Engaging in mentally stimulating activities that challenge the brain in new ways and throughout life, including through education, employment and hobbies, help to build a “cognitive reserve”. Alongside action on other key risk factors, this improves the health of brain cells, strengthens connections between brain cells, and supports the brain to maintain function, even when dementia pathologies are present (Long 2023).

Social activity

People who feel lonely or who are socially isolated are at increased risk of dementia (Livingston et al. 2024).

Some interventions that delayed cognitive decline encouraged people to connect with others by investing in existing relationships or finding new friends through hobbies, interests and volunteering (FINGERS 2025).

Cardiovascular health

What’s good for the heart is good for the brain (FINGERS 2025, Livingston et al. 2024).

Interventions that delayed cognitive decline encouraged people to quit smoking, and to monitor and control blood pressure, blood cholesterol, blood glucose and body weight (FINGERS 2025).

Mental health

Interventions that delayed cognitive decline encouraged people to relax, get good quality sleep and reduce stress to allow the brain to rest and recover (FINGERS 2025, Brodaty et al. 2025). Where needed, people were also encouraged to engage in therapies to prevent or treat depression and anxiety using cognitive behavioural therapy (Brodaty et al. 2025).

Modifiable and non-modifiable risk factors for dementia

Modifiable risk factors

Nearly half (45%) of the risk of developing dementia is potentially modifiable (Livingston et al. 2024). Modifiable risk factors are risks that can be changed if people have access to resources and support. For dementia this includes several cardiovascular and lifestyle factors (often associated with other chronic diseases) as well as social factors. For certain risk factors, such as obesity and high blood pressure, a person’s age when exposed to that risk plays a role in their likelihood of developing dementia. For other risk factors, such as traumatic brain injury or a lack of exercise, it does not matter when a person is exposed – the level of increased risk remains the same (Livingston et al. 2024).

Across the life course, risk factors with strong evidence of increasing the risk of developing dementia include:

Early life:

• low levels of education

Midlife:

• untreated hearing loss
• high cholesterol
• depression
• traumatic brain injury
• physical inactivity
• diabetes
• smoking
• hypertension
• obesity
• excessive alcohol consumption

Late life:

• social isolation
• air pollution
• untreated vision loss.

Further information on the dementia burden in Australia due to a number of modifiable risk factors is described in Dementia burden due to risk factors.

There are several other risk factors that may be associated with an increased risk of developing dementia. However, the evidence is weaker than for the risk factors listed above. They include various lifestyle and biomedical factors (such as prolonged stress, diet, inadequate sleep and health conditions, including atrial fibrillation) and environmental risks (Livingston et al. 2024, Anstey et al. 2019). Further research is needed to determine if, and how strongly, these are associated with an increased risk of dementia.

Non-modifiable risk factors

Age

Ageing is the main risk factor for dementia. While dementia can occur in people aged under 65, the risk of developing dementia doubles every 5 or 6 years for people aged over 65. However, more research is required to know if this increasing risk continues at the same rate past the age of 90 due to challenges with diagnosis in this age group (Corrada et al. 2010; Gardner et al. 2013; Slavin et al. 2013).

Genetics

Having a family history of dementia, and other genetic mutations or variations (namely, the apolipoprotein E (APOE) ε4 gene and Down syndrome) increase the likelihood of developing dementia. However, even people at increased genetic risk of dementia can reduce their likelihood of developing this condition or slow its progression through action on modifiable risk factors (Livingston 2024).

For more information on dementia among people with Down syndrome, see Dementia among people with intellectual disabilities.