Eating a traditional Mediterranean diet — rich in foods like seafood, fruits and nuts — may help reduce dementia risk by nearly a quarter, a new study finds.
Experts from Newcastle University found that people who followed a Mediterranean diet had up to a 23% lower risk of dementia than those who didn’t.
This research, published March 14, 2023, in the journal BMC medicineis one of the largest studies of its kind, as previous studies have typically been limited to small sample sizes and a low number of dementia cases.
Priority for researchers
Scientists analyzed data from 60,298 individuals from the UK Biobank, a large cohort of individuals from across the UK, who had completed a nutritional assessment.
The authors scored individuals based on how closely their diet matched key features of a Mediterranean diet. The participants were followed for almost ten years, during which time there were 882 cases of dementia.
The authors considered each individual’s genetic risk of dementia by estimating what’s known as their polygenic risk — a measure of all the different genes associated with dementia risk.
Dr. Oliver Shannon, Lecturer in Human Nutrition and Aging, Newcastle University, led the study alongside Professor Emma Stevenson and lead author Professor David Llewellyn.
The study also involved experts from the universities of Edinburgh, UEA and Exeter and was part of the Medical Research Council-funded NuBrain consortium.
Dr. Shannon said: “Dementia affects the lives of millions of people around the world and there are currently limited options to treat this condition.
“Finding ways to reduce our risk of developing dementia is therefore an important priority for researchers and clinicians.
“Our study suggests that eating a more Mediterranean diet could be a strategy to help individuals lower their risk of dementia.”
The authors found that there was no significant interaction between the polygenic risk of dementia and the associations between following a Mediterranean diet. They say this may indicate that even for people with a higher genetic risk, a better diet may reduce the chance of developing the condition.
This finding was not consistent across all analyses, and the authors suggest that further research is needed to assess the interaction between diet and genetics on dementia risk.
John Mathers, Professor of Human Nutrition, Newcastle University, said: “The good news from this study is that, even for people with a higher genetic risk, a better diet reduces the chance of developing dementia.
“While more research is needed in this area, this reinforces the public health message that we can all help reduce our risk of dementia by eating a more Mediterranean diet.”
The authors caution that their analysis is limited to individuals self-reporting their ethnic background as white, British or Irish, as genetic data was only available based on European ancestry, and that further research is needed in a range of populations to assess the potential benefit.
They conclude that, based on their data, a Mediterranean diet with a high intake of healthy plant foods may be an important intervention to include in future strategies to reduce dementia risk.
Dr. Janice Ranson, Senior Research Fellow at the University of Exeter and co-lead author of the paper, said: “The findings of this large population-based study underscore the long-term brain health benefits of consuming a Mediterranean diet rich in fruits, vegetables, whole grains and healthy fats.
“The protective effect of this diet against dementia was evident regardless of a person’s genetic risk, which is why it is likely to be a beneficial lifestyle choice for people who want to make healthy food choices and reduce their risk of dementia.
“Future efforts to prevent dementia may go beyond general advice on healthy diets and focus on supporting people to increase consumption of specific foods and nutrients essential for brain health.”
Reference: “Mediterranean Diet Adherence Is Associated with Lower Risk of Dementia Independent of Genetic Predisposition: Findings from the UK Biobank Prospective Cohort Study” By Oliver M. Shannon, Janice M. Ranson, Sarah Gregory, Helen Macpherson, Catherine Milte, Marleen Lentjes, Angela Mulligan, Claire McEvoy, Alex Griffiths, Jamie Matu, Tom R. Hill, Ashley Adamson, Mario Siervo, Anne Marie Minihane, Graciela Muniz-Tererra, Craig Ritchie, John C. Mathers, David J. Llewellyn, and Emma Stevenson, March 14, 2023 , BMC medicine.