A new study suggests that omega-3 supplements, widely marketed for brain health, may be associated with faster cognitive decline in older adults.
The research, based on data from the Alzheimer’s Disease Neuroimaging Initiative, tracked more than 800 older participants for up to five years. It found that individuals who used omega-3 supplements experienced a steeper decline in memory and thinking abilities compared to those who did not use them.
Participants were carefully matched for age, gender, genetic risk factors (including APOE ε4 status), and baseline cognitive health to ensure a fair comparison between groups.
The decline was measured using standard cognitive assessment tools such as the Mini-Mental State Examination (MMSE), ADAS-Cog13, and Clinical Dementia Rating Sum of Boxes (CDR-SB). Across all measures, omega-3 users showed a consistently faster decline over time.
Researchers noted that the pattern indicated more than normal variation, suggesting a measurable acceleration in cognitive deterioration among supplement users.
Interestingly, the effect did not appear to be linked to traditional Alzheimer’s disease markers such as amyloid plaque buildup or brain shrinkage. Instead, imaging results showed reduced cerebral glucose metabolism in brain regions typically affected in Alzheimer’s disease, based on FDG-PET scans.
However, the researchers emphasized that the findings do not establish a direct cause-and-effect relationship, as the study is observational in nature. They also highlighted limitations, including reliance on self-reported supplement use and lack of detailed data on supplement quality or oxidation levels.
While omega-3 intake from natural food sources such as fish continues to be supported by earlier research, the study raises new questions about the effectiveness and consistency of omega-3 supplements, particularly in older adults.
