Omega-3 fatty acids protect the cognitive abilities of over 60s
A diet with many polyunsaturated fatty acids protects the cognitive abilities of people over 60, and the protective effect of omega-3 fatty acids is particularly strong. Chinese epidemiologists from Qingdao University report this in Nutrition Journal.

The study

The researchers used data from 2,496 people over 60, who participated in the US National Health and Nutrition Examination Survey (NHANES) between 2011 and 2014. By means of questionnaires, the study participants had told what their diet looked like. They had also been subjected to a series of tests that psychiatrists and gerontologists use to estimate whether the cognitive abilities of the elderly are compromised.More information about those tests can be found here.
Based on the test results, the researchers divided the study participants into 4 equally sized groups. Next, they calculated the effect of the intake of omega-3 and omega-6 fatty acids on the probability of being in the group with the lowest score.
The more omega-3 and omega-6 fatty acids the study participants consumed, the less likely they were to score low on the cognitive tests. Expressed in milligrams of fatty acid, the impact of the omega-3 fatty acids was particularly significant. If you consume 1-2 milligrams of omega-3 fatty acid per kilocalorie intake per day, you're good. If you consider that alpha-linolenic acid is also an omega-3 fatty acid, then it is not that difficult to achieve that amount.

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The researchers also looked at whether the ratio between the two fatty acid types in the diet influenced cognitive abilities, but nothing came of that.Mechanism
In neuroscientific literature, the researchers found fundamental studies indicating how omega-3 fatty acids might keep brain cells healthy as the years climb. Omega-3 fatty acids are important for the functioning of neurotransmitters and also make cells more vital and robust. In addition, omega-3 fatty acids inhibit inflammatory processes that can affect brain tissue during aging processes.

The researchers do not know how omega-6 fatty acids can keep brain cells healthy.
Nutr J. 2020 Mar 28;19(1):25.