November 21, 2019
Lifestyle choices made in mid-life could have a significant impact on future dementia risk, research shows.
IPAN’s Dr Helen Macpherson (NHMRC-ARC Dementia Research Postdoctoral Fellow, Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University) is passionate about researching pathways to healthy brain ageing, and she is examining the potential for lifestyle factors such as diet and exercise to reduce dementia risk.
She is currently studying the potential benefits of a traditional Mediterranean diet, combined with regular exercise, on cognitive health in older people.
In particular, emerging evidence is showing that a person’s diet in mid-life (between 45 and 65) can influence later brain health.
“Diet is an area of importance that doesn’t get enough attention for maintaining cognitive function,” she says. “I’m really trying to build the evidence around the importance of diet for later dementia risk.”
She is focusing on increasing evidence that a plant-based Mediterranean diet is most beneficial, with more fresh produce and less processed food and refined sugar.
“We’re not talking about the Mediterranean diet that we imagine as an antipasto platter with cured meats etc, we’re talking about more of the traditional diet which is plant-based, with smaller amounts of dairy and eggs, fish, and a limited intake of red meat,” she says.
A good, nutrient rich diet may directly influence brain health; and can indirectly affect the brain by contributing to conditions such as obesity, diabetes and hypertension – which are linked to an increase risk of dementia.
While Helen is careful to say that there is no concrete action people can take as a guaranteed preventative measure against dementia, she says protective heart health behaviours from mid-40s onwards are critical.
“Brain and heart health are closely linked, so things like blood pressure, especially during mid-life, can impact on brain health,” she says. “The brain is fuelled by oxygen and glucose, which is carried by blood, so any issues with cardiovascular health can tend to have lead-on effects to the brain.”
Helen’s aim is to build on her research to develop more concrete guidelines or recommendations around diet for dementia prevention.
“Our challenge is to develop interventions that improve health across different population groups, not just to focus on narrow risk profiles,” she says.
As part of her NHMRC-ARC Dementia Research Fellowship, Helen is currently analysing the results of recently completed studies, including a randomised controlled trial looking at the effects of a six-month gym-based exercise program combined with dietary supplements on cognition in older people who are at risk of dementia. She will present preliminary findings from this study next month.
She is also working on an NHMRC Boosting Dementia Research initiative in collaboration with Swinburne University and the University of South Australia, looking at the Mediterranean diet combined with a walking program for cognition in older people residing in independent living aged care.
With a background in psychology and psychophysiology, Helen’s interest in dementia took a personal turn when her Nanna died from the condition.
But while dementia is the second leading cause of death in Australia*, she says it’s not all doom and gloom ahead.
“We’re actually seeing the rate of people developing dementia to be lower than expected in developed countries,” she says. “It’s something that we partially attribute to some of these protective lifestyle behaviours that people are taking on, such as increasing their physical activity and looking after their heart health.”
* Australian Institute of Health and Welfare report on Deaths in Australia, July 2019