The consumption of a traditional Mediterranean-type diet -rich in foods such as seafood, fruit and nuts- is associated with a lower risk of dementia, according to a study published in the journal 'BMC Medicine'.
Individuals with the highest adherence to a Mediterranean diet had up to 23% lower risk of dementia compared with those with the lowest adherence to a Mediterranean diet.
Diet may be an important modifiable risk factor for dementia that could be used to prevent disease and reduce risk, but previous studies on the impact of the Mediterranean diet have been limited to small samples and a small number of dementia cases.
Oliver Shannon and colleagues at Newcastle University analyzed data from 60,298 individuals from the UK Biobank who had completed a dietary assessment. They scored the individuals using two measures of adherence to the Mediterranean diet.
During the mean follow-up of 9.1 years, 882 cases of dementia occurred. The authors also took into account each individual's genetic risk of dementia, calculating their polygenic risk, a measure of all the different genes that are linked to dementia risk.
They found that participants with the highest adherence to the Mediterranean diet had a 23% lower risk of developing dementia compared with those with the lowest adherence score, which equates to an absolute risk reduction of 0.55%.
There was no significant interaction between polygenic risk of dementia and adherence to the Mediterranean diet, which, according to the authors, could indicate that the association between higher adherence to the Mediterranean diet and lower risk of dementia holds, regardless of the individual genetic risk of dementia.
This finding was not consistent across sensitivity analyzes, and the authors propose that further research is needed to assess the interaction between diet and genetics on dementia risk, they note.
The authors caution that their analysis is limited to individuals who reported their ethnicity as European, British, or Irish, as only genetic data based on European ancestry were available, and that further investigation is needed in a number of populations to determine the potential profit.
Thus, they conclude that, based on their data, a Mediterranean diet with a high consumption of healthy plant-based foods may be an important intervention to incorporate into future strategies to reduce the risk of dementia.
