"Flax oils vs. fish oil
In his book, Dr. Rudin (see below) points out that most Omega-3 studies are based on fish oil. Rudin finds this disappointing, as he has had better results with flaxseed oil in his own studies. This may be because flaxseed oil starts with the plant form of linolenic acid, ALA (alpha linolenic acid), whereas fish oil contains the animal form, DHA (docosahexaenoic acid). The body makes its own DHA and EPA (eicosapentaenoic acid) from ALA. Although some claim that the amount of DHA made is small, the body doesn't need much DHA. Most DHA is contained in cell membranes, and is held there with little replacement. In contrast, ALA and compounds made from it are also needed in the body for a number of essential functions. Fish oil cannot provide ALA, and therefore deprives the consumer of this critical compound. Some people feel that they need DHA or EPA as a supplement, and that's their personal choice. However, most sources covering the different types of oil indicate that plant-based Omega-3s, or ALA, is the better choice."

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