How healthy is the Extra Virgin Olive Oil?
The growing awareness of the key role that nutrition plays on the human health status and the thorough knowledge of the causes of diet-related diseases have greatly contributed to the spread of a new feeding concept: the functional nutrition. Nowadays, the foods are not exclusively a source of energy for the performance of normal metabolic processes of the body, but also the unique source of bioactive compounds, such as polyphenols, vitamins, polyunsaturated fatty acids omega-3. These compounds exert functional effects on the human organism. They contribute to "maximize" the human health status and to "minimize" the risk of occurrence of diseases. [1]
The Mediterranean diet has widely proven to prevent not only cardiovascular disease but also other chronical diseases. In fact, the Mediterranean diet has become the standard for healthy eating and a dietary template of particular value. Moreover, due to its widely proven beneficial health effects, Mediterranean diet is since 2013 inscribed on the Representative List of the Intangible Cultural Heritages of Humanity by the UNESCO [2].
This diet is based on the consumption of many daily servings of fruits and vegetables, fish, dairy products, extra virgin olive oil and a moderate dose of wine, of saturated and processed fats.
The Extra-virgin olive oil is the primary fat source and a fundamental component of the Mediterranean diet. It strongly contributes to limit the oxidative stress of the body together to make foods more attractive and appealing with its unique flavor.
The benefits of moderate consumption and balanced extra virgin olive oil have been validated by the main supervisory authorities, such as the Food and Drug Administration (FDA) and the European Food Safety Authority (EFSA). According to the FDA claims, we can reduce the incidence of coronary heart disease by taking two teaspoons a day of extra virgin olive oil. Similarly, the EFSA has approved and validated the following health claim (Commission Regulation (EU) 432/2012): ”Olive oil polyphenols contribute to the protection of blood lipids from oxidative stress. The claim may be used only for olive oil, containing at least 5 mg of hydroxytyrosol and its derivatives (e.g. oleuropein complex and tyrosol) per 20 g of olive oil. In order to bear the claim information shall be given to the consumer that the beneficial effect is obtained with a daily intake of 20 g of olive oil.”[3]
The beneficial properties related to the extra virgin olive oil consumption are ascribable to the presence in the oil of antioxidants components, such as oleuropein, hydroxytyrosol and oleocantale [4]. These phenolic compounds are characteristic and unique of the olive fruit, therefore of the extra virgin olive oil. They protect the human organism from oxidative damage caused by free radicals, thus preventing the onset of cancer, heart and neurodegenerative diseases. In particular, scientific studies show that the oleocantale possesses anti-inflammatory properties similar to that of ibuprofen, a drug for inflammatory diseases, and it is able to prevent the neurological damage due to Alzheimer's [5].
Furthermore, the presence of phenolic compounds are linked also the sensory attributes bitter and spicy, which is commonly found in virgin olive oils. For example, the oleocantale is responsible for the pungent throat exercised by some extra virgin olive oils.
However, not all extra virgin olive oils are made equal. In fact, the amount of the beneficial phenolic substances found in extra virgin olive oil can vary greatly, from 50 up to 800 milligrams per liter (ppm), depending on the combination of several factors. Among these factors, the cultivar, the degree of the olive ripeness and the technological system of processing of olives are the most important. In Italy, it is estimated about 500 varieties (cultivar) of the olive, which provide oils with different flavor and different content of phenolic substances by using the same technological process. In addition, olives at the high degree of ripeness provide oils with low content of polyphenolic substances. Finally, if the olives are processed with obsolete technology systems, in old discontinuous mills, which require a long-oil contact with the air, the phenolic substances to protect the oil from oxidation will be degraded [6,7].
As such, in order to obtain the beneficial properties of extra virgin olive oil, the consumption of "high quality extra virgin olive oil" is required. An “high quality extra virgin olive oil” can be exclusively obtained by controlling all of the factors that may affect both the nutritional and the sensory quality of the oil.
[1] N.G. Frega, D. Pacetti, E. Boselli, M.R. Loizzo. The role of omega-3 fatty acids and antioxidants in food. Progress in Nutrition (2009), 11 (3): 134-142
[2] www.unesco.org
[3] Commission Regulation (EU) 432/2012
[4] Deborah Pacetti, Paolo Lucci, Riccardo Gagliardi, Natale G. Frega.
Proceedings of 7° Convegno Nazionale ARNA. Cagliari 2-4 Ottobre 2014.
L’olio di oliva e i suoi aspetti funzionali. (The functional effects of Extra virgin olive oil). http://unica.it/UserFiles/File/Utenti/verdeoro/2014/09/ARNA2014.pdf
[5] Beauchamp G. K., Keast R.S.J., Morel D., et al., Ibuprofen-like activity in extra-virgin olive oil Nature 437, 45-46 (2005).
[6] N.G. Frega, R. Strabbioli, E. Boselli, D. Pacetti, E. Romagnoli. Caratterizzazione chimica e sensoriale dell’olio estratto dalla cultivar Leccino in funzione della tecnologia e della gramolatura. Rivista Italiana. Sostanze Grasse (2003), 80: 71-80.
[7] Michele Balzano, Deborah Pacetti, Gennaro Pieralisi, Natale G. Frega. Protoreactor®: The innovative tool to reduce processing time, increasing phenols extraction and producing a desirable extra virgin olive oil