Omega-3 levels could play a role in improving cognitive resilience in middle-aged people

Reviewed by Emily Henderson, B.Sc.Oct 5 2022

An exploratory study suggests that people who eat more foods with omega-3 fatty acids in midlife may have better thinking skills and even better brain structure than people who eat few foods with the fatty acids. The study is published in the October 5, 2022, online issue of Neurology^®, the medical journal of the American Academy of Neurology. Omega-3 fatty acids are found in fish such as salmon, sardines, lake trout and albacore tuna. They are also found in foods fortified with fatty acids or supplements.

Improving our diet is one way to promote our brain health. If people could improve their cognitive resilience and potentially ward off dementia with some simple changes to their diet, that could have a large impact on public health. Even better, our study suggests that even modest consumption of omega-3 may be enough to preserve brain function. This is in line with the current American Heart Association dietary guidelines to consume at least two servings of fish per week to improve cardiovascular health."

Claudia L. Satizabal, PhD, Study Author, University of Texas Health Science Center at San Antonio

The cross-sectional study involved 2,183 people with an average age of 46 who did not have dementia or stroke. Their levels of omega-3 fatty acids were measured. They took tests of their thinking skills. They had scans to measure brain volumes.

The people in the low group had an average of 3.4% of their total fatty acids as omega-3 fatty acids compared to an average of 5.2% for people in the high group. An optimal level is 8% or higher. Levels between 4% and 8% are considered intermediate. Levels below 4% are considered low.

Researchers adjusted for factors that could affect results. They also applied a mathematical process to normalize the data. They observed that people who ate higher levels of omega-3 fatty acids not only had higher average scores on a test of abstract reasoning, they also had larger average volumes in the hippocampus area of their brains, which plays an important role in memory.

"These results need to be confirmed with additional research, but it's exciting that omega-3 levels could play a role in improving cognitive resilience, even in middle-aged people," Satizabal said.

She noted that the study was a snapshot in time, and participants were not followed over time, so the results do not prove that eating omega-3 fatty acids will preserve brain function. It only shows an association.

While the study included a small proportion of people of many races/ethnicities, Satizabal said that the majority of the sample were non-Hispanic white adults, which may limit the ability to apply the results to other groups.

The study was supported by the National Heart, Lung, and Blood Institute, National Institute on Aging and National Institute of Neurological Disorders and Stroke.