Omega-3 & Fatty Acids
The omega-3 fatty acid is an essential fatty acid. Essential fatty acids are fatty acids which the body can't produce, and which have to be obtained through your diet or supplements. There are two essential fatty acids for humans: linoleic acid, which is an omega-6 fatty acid, and alpha-linolenic acid, which is an omega-3 fatty acid. ALA is the preliminary stage of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are the best omega-3 fatty acids for the body. The conversion rate from ALA to EPA and DHA is very low, almost non-existent (about 1-10%), which means it's best to obtain EPA and DHA directly through, for instance, oily fish or fish oil and not through ALA, which can be found in linseed oil. Omega-6 fatty acids and omega-3 fatty acids should be part of our diet in a ratio of 2:1. But the ratio has been distorted in today's western diet, which has led to us consume too much omega-6 fatty acids in relation to omega-3 fatty acids. This affects our health negatively because these two fatty acids compete for the same spaces in our cell membranes. Omega-6 fatty acids can be found in plant oils, nuts, and cereal grains. EPA and DHA, i.e., the long-chain omega-3 fatty acids, are primarily found in fish, fish oil, and shellfish. Flax and chia seeds are not good sources of the omega-3 fatty acids EPA and DHA.
Fatty acids can be found in fats and are divided usually into saturated and unsaturated fatty acids. Unsaturated fatty acids are divided further into monounsaturated and polyunsaturated fatty acids. The saturation level of a fatty acid depends on the number of double bonds in its carbon skeleton. Saturated fatty acids have no double bonds, while monounsaturated fatty acids have one double bond, and polyunsaturated fatty acids have two or more double bonds. The more double bonds a fatty acid has, the less viscous it is. Some fatty acids are vital, that is essential, like omega-3 and omega-6.