Olive oil is considered as a key component of the healthy property of the Mediterranean diet due to its fatty acid, vitamin and polyphenol composition. High monounsaturated fatty acids, and in particular oleic acid, are responsible for the benefits obtained from consuming olive oil. Also, the known benefits are considered to be due to a combination of several phytochemicals. There are more than 200 minor components in olive oil with biological activities. The most abundant antioxidants in olive oil are tocopherols, β-carotene, lutein, squalene, lipophilic and hydrophilic phenols. Phenolic acids and derivatives (vanillic acid, gallic acid), phenolic alcohols (tyrosol, hydroxytyrosol), secoiridoids (oleuropein, oleocanthal), lignans (pinoresinol), and flavones (luteolin) are phenolic compounds of olive oil. Olive oil polyphenols have antioxidant, anti-inflammatory, antimicrobial, antiviral, anti-atherogenic, anti-thrombotic, anti-mutagenic and hypoglycemic characteristics. Hydroxytyrosol, tyrosol, oleuropein and oleocanthal are the phenolic compounds that are mainly responsible for antioxidant activity, protection from blood lipid oxidation, anti-inflammatory activity, the anticarcinogenic potential, the oxidative stress resistance, and other positive impacts over human health. Additionally, olive oil contains oleocanthal, which may have an effect on several inflammatory diseases. Olive oil rich diet protects human health from cardiovascular diseases (cardiometabolic markers such as blood pressure, glycaemia and dyslipidemia, notably by reducing LDL cholesterol and LDL oxidation), type-2 diabetes, obesity, cancer, inflammation, and oxidative stress.

Source: intechopen. com