There are two essential fatty acids (essential for life) that the body cannot make; i.e., they must be obtained from foods. The best sources to obtain both essential fatty acids (linolenic-omega 3 fatty acid, and Linoleic-omega 6 fatty acid) are oils of certain seeds and nuts. The richest sources of foods containing omega 3 fatty acids are certain types of fish (mackerel, Atlantic salmon, bluefish, halibut, herring, and striped bass. Other good sources are flax seed, pumpkin, soy, and walnut. (Flax seed oil sold in stores becomes rancid very quickly and is hence not a good source of essential fatty acids).
Omega 3 fatty acids seem to help protect against heart disease by making blood less likely to coagulate; the blood is less likely to form clots that can lead to sudden death. In one study, men that eat fatty fish after a heart attack were 30% less likely to die during a two year period than heart attack victims that did not eat fish. Another study has shown that omega 3 fatty acids given before and after angioplasty help arteries remain clear rather than reclog.
Omega 3 fatty acids may aid in arthritis. In more than a dozen studies, arthritis patients ingesting omega 3 pills experienced fewer tender and swollen joints that those not taking pills. It appears that omega 3's suppress a sequence of events that occurs between the cells of the immune system and those of the joints.
Anyone considering taking omega 3 pills should consult with a physician first. Supplemental doses of omega 3's could increase bleeding during an accident of menstrual flow.