NORWOOD, MASSACHUSETTS. Dr. U.N. Das, MD of EFA Sciences LLC provides a fascinating overview of the many benefits of EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), the main components of fish oils. Dr. Das points out that an excess of tumor necrosis factor alpha (TNF) is involved in not only coronary heart disease, but also in many inflammatory diseases such as ulcerative colitis, Crohn’s disease, rheumatoid arthritis, systemic lupus erythematosus, and septic shock.
An increased intake of fish oils suppresses TNF production – a possible explanation for their beneficial effects. EPA and DHA also have a direct effect on the central nervous system. It is suggested that they increase brain levels of acetylcholine and activate the parasympathetic branch of the autonomous nervous system. This in turn leads to increased heart rate variability and a commensurate reduction in the risk of ventricular arrhythmias and sudden cardiac death. Dr. Das points out that the effect of fish oils in this respect is very similar to those obtained by exercise. EPA and DHA also act directly on individual heart muscle cells (myocytes) to suppress their tendency to go into spontaneous arrhythmia. Dr. Das emphasizes that it is important to ensure the availability of adequate amounts of arachidonic acid and dihomo-gamma-linolenic acid in the diet in order to obtain the full benefits of fish oils as preventers of arrhythmias. He also makes the intriguing observation that EPA and DHA can block the entry of sodium and calcium ions into vascular smooth muscle cells; this may be another mechanism by which fish oils help prevent ventricular arrhythmias and sudden cardiac death. Finally, Dr. Das points out that different individuals may need different doses of EPA and DHA in order to achieve their heart protective effect. [143 references]
Das, U.N. Beneficial effect(s) of n-3 fatty acids in cardiovascular diseases: but, why and how? Prostaglandins, Leukotrienes and Essential Fatty Acids, Vol. 63, December 2000, pp. 351-62