The antioxidant properties of olive oil
What are antioxidants and oxidative stress?
Oxidation is a process that occurs not only in oil extraction, but also in our own bodies. Reactions are constantly taking place in the body that lead to the formation of free radicals (peroxidants). Free radicals don't usually do much damage thanks to the protection provided by antioxidants, which help to balance them to some degree. However, if the balance is disturbed, "oxidative stress" occurs, which leads to the deterioration of normal cell functions and even cell death.
Oxidation is a complex fundamental phenomenon in the process of cell aging. Lipid or fat peroxidation tends to be proportional to the number of double bonds in a compound, which explains why oleic acid has little susceptibility to oxidation.
Cell membranes contain a large amount of fat and cholesterol, and their composition depends on nutrition. If the diet contains a lot of olive oil, the cells are more resistant to oxidation, they do not deteriorate as much and they age more slowly.
Approximately 1.5% of olive oil consists of the unsaponifiable fraction, which contains antioxidants. Virgin olive oil contains the largest amounts of these substances and other minor components.
ANTIOXIDANTS IN OLIVE OIL
Vitamin E (alpha-tocopherol), carotenoids and phenolic compounds (simple phenols like hydroxytyrosol and complex phenols like oleuropein) are all antioxidants whose activity has been demonstrated in vitro and recently in vivo, revealing further benefits in preventing certain diseases including aging .
The phenolic content of olive oils varies depending on the climatic conditions in the growing area, the time of harvest and the degree of ripeness of the olives at harvest. Oil production and storage methods also have an impact. Phenols have myriad biological properties, for example hydroxytyrosol inhibits platelet aggregation and is anti-inflammatory and oleuropein promotes the formation of nitric acid, which is a powerful vasodilator and exerts a powerful antibacterial effect.
Oxidized LDLs are known to be atherogenic, and this is where olive oil comes in as it has beneficial, protective effects against LDL oxidation. In addition, it also strengthens other cells in the body against the toxic effects of oxidants.
The high levels of antioxidants found in the Mediterranean diet appear to contribute significantly to its effect on longevity.
These antioxidants are found in fresh fruits and vegetables. Being the only oil derived from a fruit, olive oil contains a variety of substances, antioxidants and vitamins that give it extra nutritional value.
The explanation for this high level of antioxidants is probably that, being exposed to the air, the olive has to defend itself against oxygen. It therefore synthesizes a greater amount of antioxidants, which pass into the oil.
Virgin olive oil, i.e. olive oil that is not refined or industrially treated, is particularly rich in these substances and has a strong antioxidant effect, protects against damage caused by free radicals (scavenger activity) and against the development of cancer.