Your brain is 2/3 fat, while the omega-3 fatty acid (called DHA) is 20-30% of the fat in the cell membranes. While this might sound like a lot of fat, omega-3 is essential to maintain high cognitive performance and memory. It effects the transmission of nerve signals in your brain as well as the ability of cells to acquire nutrients. Neural synapses and receptors in the brain are created using fatty acids. Studies indicate that the risk of developing Alzheimer’s decreases by 60% amongst people whose diet is rich in DHA (source). DHA is one form of omega-3, besides EPA and ALA.
How does it work? — “When an electrical signal passes from one neuron to the next, it must leave a point of the cell called a synapse and traverse a gap. The signal then enters the neuron through a cell membrane, which is made of about 20 percent essential fatty acids. DHA is a fatty acid that makes the membrane flexible. Without DHA the body turns to a molecule called DPA, which is far less flexible for the task and hinders the control over electrical impulses entering the cell.” (Livestrong.com)
Unfortunately, our body cannot manufacture omega-3 on its own, so we need to include it in our diet. Foods rich in omega-3 are fish like salmon, sardines, and tuna, and organic eggs. For vegetarians, plant sources such as flax seeds and walnuts contain ALA which can be converted to DHA, but this conversion is not efficient. Interestingly, seaweed (i.e. algae) also contains small amounts of DHA which fish consume in vast amounts; in fact, algae is used in capsules for vegans. Since the majority of us lack sufficient omega-3 in our diets, supplements can be useful. Sushi – with both seaweed and fish – might be an ideal source as well!
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