In a new study, a team of scientists found that participants who used omega-3 supplements experienced faster cognitive decline than nonusers—on three standard measures.
For millions of adults, omega-3 supplements are part of a daily routine focused on heart, joint, eye and brain health.
The capsules fish oil, krill oil and flaxseed oil They are among the most used, especially among the elderly who take them in the hope of maintaining good mental health.
In a new one, published last month in The Journal of Prevention of Alzheimer’s Diseaseresearchers analyzed data from Alzheimer’s Disease Neuroimaging Initiative (ADNI), a project that tracks aging, memory, brain scans, genetics and Alzheimer’s disease.
According to , the study focused on determining whether omega-3 supplementation was associated with Alzheimer’s-related changes in cognition and brain makeup over time.
The researchers observed that the participants analyzed showed faster cognitive decline than non-users in three standard measurements.
The study began with 1814 idosos do ADNI. After matching omega-3 users with similar nonusers based on age, sex, APOE status (strongest genetic risk factor for Alzheimer’s disease), and diagnosis, the final sample included 273 supplement users and 546 non-users.
The average follow-up was 5 years and participants ranged from cognitively normal adults to people with mild cognitive impairment or Alzheimer’s disease.
One of the findings of the study came from brain imaging. The more rapid decline was not explained by the usual markers of Alzheimer’s disease, including amyloid plaques, tau accumulation, or gray matter loss.
Instead, it involved reduced glucose metabolism in brain regions vulnerable to the disease. This event was measured through PET scans with FDGwhich can reflect how well brain cells and their connections are functioning.
Despite these details, the study does not prove that omega-3 supplements cause cognitive decline.
As this is an observational study, other factors may have influenced the results. Additionally, it was not possible to fully track exact doses, long-term adherence, supplement quality, or whether some fish oil products had oxidized.
O group was also mostly white and with a high level of educationwhich may limit the scope of application of the conclusions. Omega-3 supplements should not be treated as a guaranteed strategy for brain health, especially for older adults already concerned about memory loss.
Finally, the authors reveal that further investigations are needed to understand who could benefit, who could not, and whether the risk depends on dose, supplement type, APOE status, baseline omega-3 levels, or existing brain changes.
