The hidden risk in taking omega-3 supplements: Their worrying downside,
For decades, older adults have been advised to take omega-3 supplements to strengthen bones, protect the heart and support the immune system.
But now researchers believe the supplement may have a downside – cognitive decline.
A study, published last week in The Journal of Prevention of Alzheimer’s Disease by Chinese researchers, found that older adults taking omega-3 supplements experienced faster declines in memory and thinking skills over time.
The study examined cognitive and brain imaging changes over five years in 273 omega-3 users and compared them with a control group of 546 non-users.
Participants taking omega-3 supplements were found to have experienced a more rapid decline across three major cognitive assessments. Scientists believe some omega-3 supplements may affect the way brain cells and blood vessels function in older people, potentially worsening problems with memory and thinking.
A study found that older adults taking omega-3 supplements experienced faster declines in memory and thinking skills over time
Researchers suggest the supplements may reduce glucose metabolism in the brain – the process by which brain cells generate energy
Researchers suggested the supplements may reduce glucose metabolism in the brain – the process by which brain cells generate energy – leading to poorer communication between different regions of the brain. However, experts stressed that the findings are still preliminary and do not prove fish oil directly causes cognitive decline.
And previous research has suggested the opposite – that omega-3 supplements may help protect against dementia.
A 2024 review found that diets rich in omega-3 fatty acids may modestly slow cognitive decline in some Alzheimer’s patients.
Even so, researchers are urging caution about taking omega-3 supplements specifically to try to prevent cognitive decline.
‘Omega-3 supplementation may be associated with accelerated cognitive decline in older adults, potentially through adverse effects on cerebral synaptic function,’ they wrote in their report. ‘These findings challenge the prevailing view of omega-3 as uniformly beneficial and highlight the need for a cautious reassessment of its widespread use for cognitive protection.’
