Many studies have observed that those who regularly eat fish are not only generally healthier, but they also display superior cognition. The reason for the health effects of fish on the brain is likely for two main reasons. Firstly, fish contains high amounts of dimethylaminoethanol (DMAE), and this is known to increase choline and acetylcholine levels in the brain. As acetylcholine is an important neurotransmitter that may be involved in the certain behaviours do do with motivation, and may play a key role in memory, fish consumption may facilitate cognitive improvements through this pathway. In addition, fatty fish contains long chain polyunsaturated fatty acids including docosahexaenoic acid (DHA, C22:6 (n-3)) and eicosapentaenoic acid (EPA, C20:5 (n-3)) which may be required for the correct development of neuronal connectivity and function in the brain through their physical incorporation into cell membranes and through their conversion to the eicosanoid and docosanoid hormones.
One study assessed the effects of fish consumption on the prevention of cognitive decline in a population of Chinese adults1. This study was performed on Asian adults because their diets tend to be different from Western diets, that latter already being shown to benefit from fish consumption with regard to cognitive benefits. Subjects underwent a nutritional survey and a cognitive screening test. In subjects over 65 years of age, consumption of 100 grams of fish per week was significantly protective of overall cognitive decline compared to consumption of less than 100 grams of fish per week. This protective effect was the same disparity associated with 1.6 years of advancing age. In addition, consumption of fish was also associated with significant reductions in the composite and verbal memory scores for older adults. In younger adults, aged 55-64 years, there was no significant protective effect for fish consumption. These results therefore support other data showing a protective effect for fish consumption on cognition.
RdB
