Source: Neurology, February 28, 2012; 78(9):658-64.
Research: Higher dietary intake and circulating levels of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have been related to a reduced risk for dementia, but the pathways underlying this association remain unclear. Researchers examined the cross-sectional relation of red blood cell (RBC) fatty acid levels to subclinical imaging and cognitive markers of dementia risk in a middle-aged to elderly community-based cohort. They related RBC DHA and EPA levels in dementia-free Framingham Study participants (1575; 854 women, age 67 or older) to performance on cognitive tests and to volumetric brain MRI, with serial adjustments for age, sex and education, additionally for APOE ε4 and plasma homocysteine (model B), and also for physical activity and body mass index (model C), or for traditional vascular risk factors (model D).
Results: Participants with RBC DHA levels in the lowest quartile (Q1) when compared to others (Q2-4) had lower total brain and greater white matter hyperintensity volumes. Participants with lower DHA and omega 3 index (RBC DHA+EPA) levels (Q1 vs. Q2-4) also had lower scores on tests of visual memory, executive function and abstract thinking in model A, the results remaining significant in all models.