'It is a truth, universally acknowledged,'…that olive oil is good for the health. But why? Volunteers from across Europe could soon provide the answer as they participate in a new project to investigate exactly how this Mediterranean staple benefits our health.
Specifically, the EUROLIVE project will evaluate the impact of different types of olive oil and their antioxidant phenolic compounds on oxidative stress and DNA damage.
Oxidative stress promotes the oxidation of low-density lipoproteins (LDL), a step in the development of atherosclerosis and coronary heart disease (CHD).
Olive oil is the centrepiece of the Mediterranean diet - a regime long associated with the reduced risk of disease. Scientific thought links the beneficial consumption of olive oil to its high content of monounsaturated fatty acids (MUFA) and antioxidants such as phenolic compounds, vitamin E and beta-carotene.
Under the umbrella of EUROLIVE, a total of 180 healthy volunteers in northern, central and southern Europe will take a daily 'dose' of 25ml - close to the amount used daily in Mediterranean countries - of either refined (without phenolic compounds), common (with low phenolic content) or extra virgin (with high phenolic content) olive oil per day.
The objectives of the study, co-ordinated by Dr María Isabel Covas at the Institut Municipal d'Investigació Mèdica in Barcelona, Spain, are to compare the impact of these oils on oxidative damage and LDL fatty acid composition. In addition, the scientists are looking to investigate the bioavailability of olive oil phenolic compounds in humans, to determine the relationship between olive oil ingestion and the binding of phenolic compounds to LDL, and to explore differences in lipid peroxidation and fatty acid composition of LDL among healthy men from different European areas.
Finally they are hoping to determine whether addition or substitution of MUFA in the diets of participants from central and northern Europe results in a more favourable plasma LDL fatty acid composition after three months of consuming the olive oil.
To date, the project investigators have prepared the olive oils to be used for the study, carried out a pilot study on the bioavailability of the olive oil phenolic compounds, and a method has been developed to measure the plasma concentrations of the olive oil compounds tyrosol and hydroxytyrosol.
Updates on the European funded project can be obtained from the project website.