The Importance of the Omega-6/Omega-3 Fatty Acid Ratio in Cardiovascular Disease and Other Chronic Diseases

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Experimental Biology and Medicine (Impact Factor: 2.17). 07/2008; 233(6):674-88. DOI: 10.3181/0711-MR-311
Source: PubMed


Several sources of information suggest that human beings evolved on a diet with a ratio of omega-6 to omega-3 essential fatty acids (EFA) of approximately 1 whereas in Western diets the ratio is 15/1-16.7/1. Western diets are deficient in omega-3 fatty acids, and have excessive amounts of omega-6 fatty acids compared with the diet on which human beings evolved and their genetic patterns were established. Excessive amounts of omega-6 polyunsaturated fatty acids (PUFA) and a very high omega-6/omega-3 ratio, as is found in today's Western diets, promote the pathogenesis of many diseases, including cardiovascular disease, cancer, and inflammatory and autoimmune diseases, whereas increased levels of omega-3 PUFA (a lower omega-6/omega-3 ratio), exert suppressive effects. In the secondary prevention of cardiovascular disease, a ratio of 4/1 was associated with a 70% decrease in total mortality. A ratio of 2.5/1 reduced rectal cell proliferation in patients with colorectal cancer, whereas a ratio of 4/1 with the same amount of omega-3 PUFA had no effect. The lower omega-6/omega-3 ratio in women with breast cancer was associated with decreased risk. A ratio of 2-3/1 suppressed inflammation in patients with rheumatoid arthritis, and a ratio of 5/1 had a beneficial effect on patients with asthma, whereas a ratio of 10/1 had adverse consequences. These studies indicate that the optimal ratio may vary with the disease under consideration. This is consistent with the fact that chronic diseases are multigenic and multifactorial. Therefore, it is quite possible that the therapeutic dose of omega-3 fatty acids will depend on the degree of severity of disease resulting from the genetic predisposition. A lower ratio of omega-6/omega-3 fatty acids is more desirable in reducing the risk of many of the chronic diseases of high prevalence in Western societies, as well as in the developing countries.

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Available from: Artemis Simopoulos, Aug 18, 2015
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    • "Improving the dietary omega-6:omega-3 ratio by increasing omega-3 fatty acid intake is essential for optimal brain function and for the management of cardiovascular disease, arthritis and cancer (Simopoulos, 2008). "
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    Affiliation: NZIC Oils and Fats Group
    • "Among the effects that may contribute to decrease cardiovascular risk, n-3 and n-6 PUFAs have been related with lipid metabolism, alteration of plasma triglycerides, and influence on atherosclerosis (Simopoulos, 2008). The interplay of both n-3 and n-6 PUFA may determine impaired regulation of hepatic and adipose function through inhibiting or enhancing an inflammation status, ectopic fat accumulation in liver (non-alcoholic fatty liver disease [NAFLD]), and development of hepatic fibrosis to finally nonalcoholic steatohepatitis (NASH) (Scorletti and Byrne, 2013). "
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    • "Beef produced from cattle at pasture has desirable nutritional characteristics and is increasingly valued by consumers as it tends to have higher levels of polyunsaturated fatty acids (PUFAs) and lower ratios of n-3 : n-6 FAs (Schmid et al., 2006; Fincham et al., 2009; Duckett et al., 2013). Research with humans suggests that a lower ratio of n-3 : n-6 FAs is desirable for reducing the risk of many chronic diseases such as cardiovascular disease, cancer, inflammatory and autoimmune diseases (Simopoulos, 2008). Diet could influence FA profile of meat and some research indicates that feeding cattle at pasture compared with typical feedlot diets results in greater concentrations of conjugated linoleic FA (CLA) and more favorable ratio between n-6 : n-3 in beef. "
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