Personal lifestyle choices alone insufficient to prevent dementia, study finds

Personal preventative measures alone will not decrease the risk of dementia, researchers have found.

Until now there has been a focus on personal choices such as eating, exercise, social activity and mental health to prevent Australia's leading cause of death.

But a Dementia Australia-funded research paper from Curtin University has found that such efforts may have led to the social, environmental and policy influences that shape brain health being overlooked.

In 2024, a landmark study identified 14 potentially modifiable risk factors for dementia, including high blood pressure, diabetes, cholesterol, physical inactivity, smoking and hearing loss.

It found many must be tackled in midlife and could potentially prevent 45 per cent of dementia cases.

In the new paper published in the peer-reviewed medical journal The Lancet, researchers mapped 61 risk factors ranging from lifestyle to socio-economic status.

Of those, 49 (80 per cent) were at the individual level. Far fewer related to the interpersonal or societal levels.

The researchers found far less attention was paid to education, housing, neighbourhood safety, healthcare access, clean air and social connections, "despite growing evidence these factors affect people’s ability to protect their brain health".

"For example, we tell people they need to be physically active, but being physically active can depend on having a safe environment and access to places that are safe to exercise in and affordable," study author Jennifer Dunne said.

“[The 14 factors] are obviously important for a range of reasons, but our study shows that many of the factors that shape dementia risk do not sit solely within an individual’s control."

University of NSW cognitive disorder researcher Simone Reppermund, who was not involved in the study, said the paper highlighted the need for greater understanding of the role sociological, economic and environmental factors played in dementia prevention.

"Often the message goes out that it is actually on the individual to change something, but many important factors that actually are very much interlinked and interconnected with these individual behaviours are neglected or not even looked at in research, and especially in policy," she said.

"This is harder to do because it changes from society to society, and then you have high-income and low-income countries, but it is definitely an important way to go forward."

About 446,500 people are living with dementia in Australia and that figure is projected to exceed one million by 2065, according to Dementia Australia.

Dementia is the decline in the ability to think, remember and reason to the extent that it interferes with a person's daily life and activities, the National Ageing Research Institute said.

"There is a lot more focus now on dementia and how to prevent it, because dementia is a huge economic burden, a huge health burden, and it affects not only the individual but the whole family and the whole society," Dr Reppermund said.

Dr Dunne said it hoped the latest research findings would inform prevention policy.

"The research has been very valuable to get us to this point," she said.

"What we're now saying is that it does need to go further, and that if we really want to be talking about preventing dementia and improving brain health at a population level, we need ot look at the whole population and how the individual lives within that."