A study suggests that adhering to a diet reminiscent of the traditional Mediterranean style, which includes an abundance of seafood, fruits, and nuts, could potentially reduce the risk of developing dementia by nearly one-quarter. Researchers from Newcastle University discovered that individuals following a diet similar to the Mediterranean model experienced a risk reduction for dementia of up to 23% compared to those who did not follow such a diet.

Published in BMC Medicine, this research stands out due to its scale. Past investigations into the topic have typically been constrained by smaller sample sizes and a limited number of dementia cases. This study significantly advances the understanding of the potential dietary influences on dementia risk.

The study’s methodology involved analyzing data from 60,298 UK Biobank participants, representing a broad cross-section of the UK population who had previously submitted detailed dietary information. The researchers assessed the participants’ diets based on their adherence to the critical characteristics of a Mediterranean diet. They followed the participants for nearly a decade, during which 882 instances of dementia were recorded.

An innovative aspect of the study was considering each participant’s genetic predisposition to dementia. This was evaluated through a polygenic risk score, which aggregates the impact of various genes associated with the risk of developing dementia.

The research team, led by Dr Oliver Shannon, Professor Emma Stevenson, and Professor David Llewellyn as joint senior authors, collaborated with experts from Edinburgh, UEA, and Exeter. This work is part of the Medical Research Council-funded NuBrain consortium.

Dr Shannon highlighted the importance of finding strategies to mitigate the risk of dementia, given the condition’s significant impact worldwide and the current lack of effective treatments. He emphasized that adopting a diet more aligned with Mediterranean principles could be a viable approach to reducing the risk of dementia.

The study found no significant interaction between the genetic risk of dementia and the positive effects of adhering to a Mediterranean diet. It suggests that even individuals with a higher genetic risk might lower their chances of developing dementia by improving their diet. However, the authors acknowledge the need for further research to explore the relationship between diet, genetics, and dementia risk more thoroughly.

Professor John Mathers reflected on the encouraging implications of the study, reinforcing the message that a better diet can decrease the likelihood of dementia, even among those at higher genetic risk. He advocated for more research to bolster the case for public health interventions focusing on dietary improvements.

The researchers caution that their findings primarily apply to white, British, or Irish individuals due to the study’s reliance on genetic data from European ancestry. They call for further investigation across diverse populations to fully understand the potential benefits of a Mediterranean diet in reducing dementia risk.

Concluding their findings, the authors propose that a diet rich in healthy plant-based foods, characteristic of the Mediterranean diet, should be considered an essential component of future strategies to lower the risk of dementia.

Dr Janice Ranson, a joint lead author from the University of Exeter, emphasized the long-term brain health advantages of consuming a Mediterranean diet. She suggested that future efforts to prevent dementia could extend beyond general healthy eating advice to include specific recommendations on increasing the intake of foods and nutrients vital for brain health.

More information: Oliver M. Shannon et al, Mediterranean diet adherence is associated with lower dementia risk, independent of genetic predisposition: findings from the UK Biobank prospective cohort study, BMC Medicine. DOI: 10.1186/s12916-023-02772-3

Journal information: BMC Medicine Provided by Newcastle University