Mediterranean diet linked to slower brain ageing in new study

A BMJ study of 1,647 middle-aged and older adults followed for a median of around 12 years found greater adherence to a Mediterranean diet was associated with a slower decline in total grey matter volume. Researchers cautioned the study does not prove a direct protective effect and did not assess memory or thinking.

A new study published in the British Medical Journal reports an association between Mediterranean-style eating and slower signs of brain ageing. The diet — known for olive oil, fish, vegetables and low processed fats — has been linked previously to lower risk of heart disease and metabolic conditions. The BMJ analysis followed 1,647 middle-aged and older people over a median period of around 12 years and was carried out by a multinational team led by Changzheng Yuan. Earlier research, including a 2024 study of about 92,000 people, reported higher olive oil intake was associated with lower dementia-related mortality. Key findings: - The study assessed health and imaging data for 1,647 middle-aged and older participants with a median follow-up of around 12 years. - Greater adherence to a Mediterranean diet was associated with a slower decline in total grey matter volume, according to the researchers. - The research team included experts from Zhejiang University School of Medicine, Harvard T.H. Chan School of Public Health, Boston University School of Medicine, Harbin Institute of Technology and the University of Edinburgh. - Authors and commentators noted the study cannot prove a direct protective effect and it did not measure impacts on memory or thinking. - Alzheimer's Research UK said the findings add to growing indications that balanced diet and other healthy steps may support brain health as people age. Summary: The BMJ study adds to evidence linking Mediterranean-style eating with structural brain measures in middle-aged and older adults, suggesting slower reduction in grey matter volume among those with greater adherence. Researchers and outside commentators emphasize the association is not proof of causation and call for more long-term studies in diverse groups to better understand the roles of diet, genetics and other factors.