Olive Oil Polyphenols

Olive oil polyphenols

In addition to vitamins, trace elements, minerals and the health - boosting monounsaturated fats, the exquisite olive oil is rich in polyphenols, responsible for its nutritional excellence. Polyphenols, as we will see next, do not protect the human body alone; they also protect the olive oil itself from getting oxidized, which is why it has such a long shelf life (at least 18 months and in some cases more) and is stable at high temperatures. Thus, it is the most suitable oil for cooking, because as its quality and nutrients do not get easily affected.

ΤIP: An olive oil that is rich in polyphenols has a spicy finish, like a slight burning sensation in the throat, and a pleasantly bitter taste at the base of the tongue. This is because its organoleptic properties (aroma, taste) are affected by polyphenols, especially by oleocanthal. This feature is usually intense in early harvest olive oil (agourelaion).

Not all olive oils have the same polyphenol content. Factors such as the variety of the olive tree, the soil, the microclimate, the stage of ripening of the fruit, the cultivation method, as well as of the production and storage of the olive oil, play a part therein. The type of olive oil that is usually rich in polyphenols, given the factors mentioned, is the extra virgin olive oil produced by cold extraction. That is, where the temperature does not exceed 27 degrees Celsius during the process of olive paste malaxation. Even higher phenolic content is present in “agourelaio”, early harvest olive oil, although this is not always certain and depends on the above factors.

Fact: In a mapping research on Greek olive oil (Karkoula et al., 2014), that studied the content of olive oil in phenolic components by region and by variety, among 291 samples of Greek production extra virgin olive oil, the highest content in phenols on average, was found in the Koroneiki variety.

Health Shield

According to Regulation no 432/2012 of the European Commission, olive oils with high phenolic content are allowed to bear the following health claim: “Olive oil polyphenols help protect blood lipids from oxidative stress”. Through this distinction, a new category of super olive oil emerges; this way, from a food product, olive oil is transformed into a functional foodstuff with health -protective properties. This claim is permitted, provided that the olive oils contain at least 5 mg of hydroxytyrosol and its derivatives (e.g. a complex of olive oil and tyrosol) per 20g of olive oil. The beneficial effects occur when the consumer takes in at least 20g of olive oil per day, in the context of a generally balanced and healthy lifestyle and diet.

What this means practically: The claim acknowledges the ability of polyphenols to reduce LDL oxidation, as they cleanse the body of free radicals, resulting in the reduction of cholesterol deposited in the tissues. They also act against the epithelial tissue oxidizing agents. As a result, the chances of developing atherosclerotic plaque leading to atherosclerosis are reduced, in turn reducing the risk of cardiovascular disease (contributing to the prevention and treatment of heart disease). In addition to protecting the cardiovascular system, many studies have associated olive oil phenols with protection against thrombosis, liver disease, hypertension, diabetes, cancer, leukemia, osteoporosis, Alzheimer's disease, stroke, the metabolic syndrome etc.

Olive oil polyphenols under the microscope

Simple phenols such as hydroxytyrosol, tyrosol, vanillin, secoiridoids such as oleocanthal, oleasin, eleuropein aglucone (aldehyde form), ligstroside aglucone (aldehyde form), lignans and flavonoids, are the main categories of olive oil polyphenols. Oleocanthal, oleasin and, secondarily, eleuropein and ligstroside aglucones, are the major derivatives of hydroxytyrosol and tyrosol. Oleocanthal (Oleocanthal = decarboxymethyl ligstroside aglycone) is responsible for the burning sensation in the throat (pungency), especially in early harvest olive oil. It has the same effect as ibuprofen, acting as a natural anti-inflammatory (Beauchamp G. et al. 2005).

TIP: Chronic exposure to low doses of antioxidants / anti-inflammatory substances, such as oleocanthal, offers protection against cardiovascular disease and aging.

Research has shown that oleocanthal acts as an antioxidant, helps inhibit or even reverse the progression of Alzheimer's disease in animals and acts against cancer cells in many cancers, limiting the further growth of tumors. It is a natural inhibitor of the enzymes COX1 and COX2, which are responsible for triggering pain, inflammation and fever, and can act as a therapeutic agent in the treatment of rheumatoid arthritis.

Oleasin has a structure similar to that of oleocanthal, as well as anti-inflammatory, antimicrobial and antioxidant properties, with a possible contribution to the treatment of neuroinflammatory diseases. It has a potential role in inhibiting the progression of atherosclerosis, a potential utility in reducing the risk of ischemic stroke and it protects red blood cells from oxidation, even at low doses. It also seems to help restore biological functions and protect endothelial progenitor cells from aging - the endothelium is an organ covering the inner surface of blood vessels like a membrane. Apart from its other functions, it produces substances that improve blood flow, which is significant for maintaining heart health.

Eleuropein aglucone (aldehyde form) has a strong antioxidant effect and helps protect against Alzheimer's disease, as shown by animal studies, and against type 2 diabetes. Ligstroside aglucone (aldehyde form) acts as an antioxidant and has shown anti-metastatic action against cancer cells in breast cancer, as well as growth inhibition action in the same type of cancer. Research into the properties of valuable polyphenols is ongoing.

Attention: The above article / content is for informational purposes only. Before using any recipe, or before changing your eating habits, consult with your healthcare professional or nutritionist. If you are taking medication, make sure there are no side effects.