A longitudinal study using data from the Alzheimer’s Disease Neuroimaging Initiative found that omega-3 fatty acid supplementation was associated with accelerated cognitive decline in older adults, challenging the common belief that omega-3 universally protects brain health. Participants taking omega-3 supplements showed faster worsening in MMSE, ADAS-Cog13, and CDR-SB scores over time. Interestingly, the association was not explained by classical Alzheimer’s disease pathologies such as amyloid-β accumulation, tau deposition, or gray matter atrophy. Instead, reduced cerebral glucose metabolism on FDG-PET scans—reflecting impaired synaptic and neuronal function in AD-vulnerable brain regions—partially mediated the relationship, accounting for 19% to 41% of the observed cognitive decline. These findings suggest that omega-3 supplementation may adversely affect cerebral synaptic function in some older adults and highlight the need for a more cautious reassessment of its widespread use for cognitive protection. Source: https://www.sciencedirect.com/
