The consumption of fish has played an important role in the evolution of humans. The human brain consists approximately of 60% fat. Fatty acids called ALA, DHA and EPA are concentrated in cell walls and the myelin sheaths of the neurons. These long-chain fatty acids have an unsaturated double bond in the third carbon from the end, and thus are known chemically as omega-3 fatty acids. These fats are essential for good health and must be included in the diet because the body cannot create them from other fats. Some vegetable sources, such as walnuts and flax seed, contain ALA, but fish oil is the best source of DHA and EPA. The body can convert ALA to DHA and EPA, but not very efficiently.
Omega-3 fatty acids are components of all cell membranes and a deficiency of these essential fatty acids can cause symptoms such as fatigue, poor memory, dry skin, heart problems, depression, and bad circulation. Fish oil supplementation is generally safe when taken in low doses (3 grams or less per day), but there are some safety concerns when fish oil is taken in high doses because it may keep blood from clotting and can increase the chance of bleeding, particularly in combination with anticoagulants and blood thinners.
It is always better to get nutrients from foods rather than from supplements. Natural foods, such as salmon, herring or other fish, have the essential fatty acids, but they also have protein, vitamins and minerals necessary for a healthy diet. The picture above shows an open-faced sandwich with slices of smoked salmon on sour dough bread spread with a teaspoon of mustard, and garnished with slices of avocado and chopped dill. This is a delicious way of getting your omega-3 fatty acids.