Health and Medicine
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Omega-3 supplements are considered by many to be a good choice for brain health, but a new study suggests that may not always be the case. In older adults, the researchers found, omega-3s might actually accelerate cognitive decline, indicating the need for a fresh look at dietary advice around these supplements.
The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.Omega-3 polyunsaturated fatty acids (PUFAs) are essential fats that the human body needs for things like building cell membranes. Unfortunately for us, our bodies aren’t great at producing them, which means we need to get them from our diet. Sources include oily fish, nuts, and seed oils, but supplements are also popular.
Anyone try and force you to eat cod liver oil as a kid? That’s omega-3.
There have been tons of studies investigating various potential benefits of incorporating more omega-3 into your routine, mostly focusing on heart health. But another big area of research has been the brain, specifically whether increasing consumption of essential fatty acids through diet or supplements could be protective against the effects of brain aging.
A Cochrane Review in 2012 concluded that the available evidence at the time “showed no benefit of omega-3 PUFA supplementation on cognitive function in cognitively healthy older people.” Since then, some studies have suggested that certain omega-3 and omega-6 fatty acids could help ward off cognitive decline and dementia as people age, but results remain mixed.
The new study comes from a team of scientists based in Chongqing, China, using data from the Alzheimer’s Disease Neuroimaging Initiative. With this longitudinal data, they set out to analyze the relationship between omega-3 supplementation and cognitive decline over time, and how this intersects with the pathological processes that typically happen in the brain with Alzheimer’s disease.
Rather than any kind of protective or even a neutral effect, the study concluded that supplementing extra omega-3 could actually speed up cognitive decline in older adults. The authors write that “the cognitive impact of omega-3 in aging brain may be more complex and context dependent than previously assumed.”
The team used three different rating scales to evaluate cognitive decline. A range of different omega-3 supplements were represented, such as fish oil and flaxseed oil. They estimated that based on each of the three rating systems, omega-3 use corresponded to approximately 7.8 percent, 15 percent, and 10.7 percent of the yearly Alzheimer’s disease progression in these patients.
Interestingly, the authors believe that this extra cognitive decline was not driven by the same mechanisms that cause decreasing brain function in Alzheimer’s. The evidence instead points to omega-3 supplementation causing issues with synapses, the junctions between brain cells that need to be working properly for information to be efficiently transmitted.
“These findings raise important questions about the traditional assumption that omega-3 fatty acids exert uniformly neuroprotective effects,” the authors write, adding that “our results suggest a previously underrecognized possibility that omega-3 supplementation may, in some contexts, adversely affect synaptic integrity, ultimately counteracting its short-term benefits.”
“From a clinical and public health standpoint, our findings suggest that a more nuanced assessment and further research are warranted, regarding the widespread use of omega-3 supplements for cognitive protection.”
Future studies will investigate this further, but it appears that omega-3 supplements may not be the simple brain health boost that we may have hoped for.
The study is published in The Journal of Prevention of Alzheimer’s Disease.
The content of this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.
