High Omega-6/Omega-3 Fatty Acid Ratio Diets and Risk of Noncommunicable Diseases: Is the Tissue, the Main Issue?

Abstract

Abstract Epidemiological studies indicate that social determinants of health such as lifestyle and food consumption patterns may be important in the pathogenesis of noncommunicable diseases (NCDs). In developed countries, when people learned the methods of prevention, there was a decrease in cardiovascular diseases (CVDs). However, a large number of people continue to suffer from other NCDs due to increase in obesity and metabolic syndrome. The Western-type diet is generally proatherogenic characterized with energy dense, refined, ready-prepared foods with a high glycemic index and unhealthy lipids poor in ω-3 fatty acids, phytochemicals, and fiber. A high omega-6/omega-3 ratio, as found in today’s Western diets, promotes the risk of NCDs. These diets are rich in total fat, trans fat, refined carbohydrates and the ω-6/ω-3 fatty acid ratio varies from 20 to 50 in various countries. Increased intake of such diets is associated with the proinflammatory state in our body, with increase in oxidative stress, free fatty acids, and triglycerides; resulting in endothelial dysfunction, leading to CVDs and other chronic diseases. Both omega-6 and omega-3 fatty acids influence gene expression. Omega-3 fatty acids have strong antiinflammatory effects whereas ω-6 fatty acids are proinflammatory. A high ω-6/ω-3 ratio of the diets and tissues have been reported as a risk factor of coronary artery disease (CAD), hypertension, atherosclerosis, stroke, type 2 diabetes mellitus, cancer, and other chronic diseases. Increased dietary intake of ω-6 fatty acid significantly enhances the apparent atherogenic effect of genotype, whereas increased dietary intake of omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) blunts this effect. Recent studies indicate that dietary omega-6 fatty acids promote, whereas marine omega-3 fatty acids EPA and DHA inhibit leukotrienes-, thromboxanes-, prostaglandins-mediated tissue inflammation thereby leading to the pathogenesis of NCDs. It is possible that proinflammatory diets and inflammation in the tissue are the main issues for development of NCDs. New approaches including Mediterranean-type diets rich in fruits, vegetables, nuts, canola oil, olive oil characterized with low ω-6/ω-3 ratio in the diet, may modulate inflammation and may be protective for body tissues.