Importance of lipids in the nutritional treatment of inflammatory diseases.

Over the last decades, scientific advances in the knowledge of anti-inflammatory properties of lipids have lead to the development of new formulas for enteral and parenteral nutrition. These products have been utilised as a treatment for a variety of inflammatory diseases. In this review we expose the effects of lipids used in enteral nutriton on different inflammatory pathologies such as inflammatory bowel disease, atherosclerosis, lung fibrosis, rheumatoid arthritis, and others. During inflammatory diseases, eicosanoids are produced from polyunsaturated fatty acids present in cellular membranes. Inflammatory activity of these molecules depends on the nature of their precursors: when arachidonic acid (n-6) is present, pro-inflammatory molecules are released, whereas eicosapentaenoic acid (n-3)-derived eicosanoids are weakly inflammatory. In this way, fish oils, rich in n-3 polyunsaturated fatty acids, increase the content of eicosapentaenoic-eicosanoids and decrease arachidonic acid in immune and endothelial cells leading to a lower inflammatory activity. Likewise, oleic acid exhibits anti-inflammatory effects by preventing the release of particular chemotactic molecules. In summary, enteral diets supplemented with n-3 polyunsaturated fatty acids and oleic acid benefits the treatment of patients with inflammatory pathologies, leading to better outcomes, and decreasing the doses of anti-inflammatory drugs, which exhibit important secondary effects.