The omega-3 index: new risk factor for a healthy heart?
Low omega-3 levels: future problem for healthy hearts in the present
Scientific evidence shows that the level of omega-3 fatty acids in the blood may be a new risk factor and proposes a new diagnostic tool-the Omega-3 Index-that can be used easily by anyone. This new diagnostic tool, consisting of a quantification of the fatty acid profile in an individual, could help physicians and patients at risk of heart disease achieve the adequate levels of omega-3 fatty acids that latest scientific research shows ensure a measurable reduction in the risk of heart attack and sudden mortality. "To address the problem of so-called 'bad cholesterol' (LDL) in the future, cardiologists' associations could rightly recommend EPA and DHA consumption as a crucial therapeutic intervention to support heart health," write Clemens von Schacky of the Ludwig-Maximilians-Universitat in Munich and Prof. William Harris of the University of South Dakota. Numerous research studies over time have matched omega-3 fatty acid consumption with a whole range of beneficial effects: for heart health, optimal development of the unborn child during pregnancy, joint health, improved mood and behavior, and prevention of certain types of cancer.
The new review of studies published online in Cardiovascular Research looked at a set of epidemiological studies and four large-scale intervention studies and concluded that scientific evidence supports the benefits of omega-3 consumption on heart health. The mechanism behind these beneficial effects is believed to be the incorporation of EPA and DHA at the level of heart cell membranes, explain researchers Von Schacky and Harris. These fatty acids go on to replace those present by positively altering the properties of the cells themselves. The changes in question involve dilation of blood vessels in favor of improved blood flow. This is followed by a reduction in inflammatory events and a lowering of blood triglyceride levels.
Given that omega-3s become part of the composition of cell membranes, it could be critical to measure omega-3 content at the level of cardiac cells as a primary marker of cardiovascular risk, argue Von Schacky and Harris. "The possibility that omega-3 may serve as a biomarker and thus have clinical prognostic utility should be seriously considered." Right on the heels of the above observations, Von Schacky and Harris propose the "omega-3 index" defined as the percentage of EPA and DHA relative to the other categories of fat present at the red blood cell membrane as a new diagnostic tool in primary prevention.
Based on data in the scientific literature, the researchers calculated that an omega-3 index of 8 percent or higher is relatable to a 90 percent reduction in the risk of sudden cardiac death compared with a value of 4 percent or lower. "A standard dose of one gram of omega-3 per day, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), recommended by cardiologists' associations is probably far from the ideal omega-3 intake for each of us, since not only the standard dose but also the type of diet, our genetic background, body mass index and the association of many other factors underlie the omega-3 fatty acid profile of a given person," the scholars write.
he risk of finding pollutants in oily fish such as mercury, dioxins, and polychlorinated biphenyls (PCBs) has led some to reduce consumption of fresh fish despite opposing considerations that the benefits far outweigh the risks. At the same time, consumers are increasingly seeking omega-3s from safer sources. Von Schacky and Harris recommend that pollutants should be categorically avoided.
Source:
Wolk A, Larsson SC, Johansson JE, Ekman P. Long-term fatty fish consumption and renal cell carcinoma incidence in women. JAMA. 2006 Sep 20;296(11):1371-6.
