Mediterranean diet and health: Biological importance of olive oil

Olive oil, the main fatty component of the Mediterranean diet, is character ized by consisting of monounsaturated fatty acids as well as by its elevate d content in antioxidant agents. This oil exhibits numerous biological func tions which are beneficial for the state of health. A diet rich in monounsa turated fatty acids provides an adequate fluidity to the biological membran es, diminishing the hazard of lipid peroxidation which affects polyunsatura ted fatty acids. Moreover, the antioxidants present in olive oil are able t o scavenge free radicals and afford an adequate protection against peroxida tion. Regarding the heart, olive oil decreases the plasmatic levels of LDL- cholesterol and increases those of HDL-cholesterol, hence diminishing the r isk of suffering from heart complaints. In this context, it has been sugges ted that increased consumption of monounsaturated fatty acids in place of p olyunsaturated fatty acids will render circulating lipoproteins less sensit ive to peroxidation and thereby diminish the development of atherosclerosis . Olive oil has also been proven to contribute to a better control of the h ypertriglyceridemia accompanying diabetes and may reduce the risk of breast cancer and colorectum. On the other hand, several investigations have sugg ested that olive oil can be beneficial in inflammatory and autoimmune disea ses, such as rheumatoid arthritis. In this sense, some reports have indicat ed that olive oil modifies inflammatory cytokines production. As for the di gestive system, olive oil enhances gallbladder emptying consequently reduci ng cholelithiasis risk, decreases the pancreatic exocrine secretion and gas tric secretory function in response to food. Finally, it has been demonstra ted that a diet rich in olive oil is associated with a high percentage of g astric ulcer healing and affords a higher resistance against non steroidal antiinflammatory drugs-induced gastric ulcerogenesis.