PORTUGAL: Olive oil - research reveals the good bits

A study of the major antioxidants in olive oil has pinpointed the one that has the most health benefits.

Scientists from the University of Porto found that the antioxidant DHPEA-EDA gave the greatest protection from heart attack and stroke.

Lead researcher, Fatima Paiva-Martins, said the research provided the scientific basis for the clear health benefits seen in people who have olive oil in their diet. Paiva-Martins is an assistant professor in the faculty of sciences at the University of Porto and a researcher in the university's chemistry research centre.

She and her colleagues compared the effects of four related polyphenolic compounds on red blood cells subjected to oxidative stress by a known free radical generating chemical.

Free radicals, acting on LDL or 'bad' cholesterol contribute to heart disease and hardening of the arteries. Red blood cells are particularly susceptible to oxidative damage because they are the body's oxygen carriers.

The scientists found DHPEA-EDA was the most effective of the four compounds and protected red blood cells even at low concentrations. They said virgin olive oils contained increased levels of DHPEA-EDA compared with other oils and could account for as much as half the total antioxidant component of such oils.

Paiva-Martins said the findings could lead to the production of "functional" olive oils specifically designed to reduce the risk of heart disease.

"Now we have identified the importance of these compounds, producers can start to care more about the polyphenolic composition of their oils," she said.

The research was published in Molecular Nutrition & Food Research.