Eicosapentenoic acid and Docosahexenoic acid, usually referred to as omega-3 fatty acids or fish oils, are normal constituents of our cells. They are particularly abundant in brain cells, nerve relay stations (synapses), adrenal glands, visual receptors (retinas), and sex glands-the most biochemically active tissues of our bodies.

They are manufactured from the essential fatty acid alpha-linolenic acid (LNA), found in abundance in flax, hemp seed, soy beans, walnuts, dark green leaves and canola oil. EPA and DHA are found ready-made in cold water fatty fish such as mackerel, salmon, trout, sardines and tuna. One of their important properties is a tendency to disperse, or move away from other molecules of EPA and DHA, dragging along saturated fatty acids and cholesterol and thus preventing their aggregation-the first step towards averting clogged arteries (for more on this subject, see under Linoleic acid).

EPA and DHA have very important applications. They prevent platelets from sticking together, thus lowering the risk of clots that could cause heart attacks or strokes. They appear to reduce apoprotein(a) and fibrinogen, two repair proteins involved in the presence of excessive atherosclerotic tissue in arteries, and hence helping to maintain the arteries open. They can reduce blood triglycerides by as much as 65 percent, and lower cholesterol, low-density lipoprotein, and very low-density lipoprotein, thus reducing the risks of high blood pressure, atherosclerosis, heart and kidney failure, and stroke. EPA decreases high blood pressure through the production of series 3 prostaglandins (PG3), which block or moderate the production of blood pressure-raising series 2 prostaglandins (PG2), made from omega-6 fatty acids (seed oils). This blocking effect of EPA-derived PG3, helps prevent strokes, heart attacks, and diabetic complications like gangrene and blindness. There is also evidence that omega-3 fish oils inhibit tumor growth and metastatic cancer. Other conditions where fish oils are helpful are bipolar disease, lupus, menstrual problems, osteoporosis, Reynaud's phenomenon, rheumatoid arthritis. Fish oils seem to initially raise low-density lipoprotein counts, but this is only a temporary phenomenon.

Fish oil supplements are safe, but it is essential that they be fresh, as they deteriorate rapidly. If you are on blood-thinning medications, or a diabetic, consult an experienced health professional before taking fish oil supplements.