Olive oil really does get rid of 'bad' cholesterol, say researchers in Barcelona

Researchers at Barcelona's Hospital del Mar Institute of Medical Investigations (IMIM) found that a diet rich in extra-virgin olive oil improves the work of high-density lipoproteins (HDLs, known as 'good cholesterol').

The job of HDLs is to extract 'bad' cholesterol from the arteries and transport it to the liver, which eliminates it from the body.

And according to the findings published in Circulation magazine, extra-virgin olive oil heightens the ability of HDLs to do this, making elimination of 'bad' cholesterol more effective and complete.

Until now, says the IMIM team, the benefits of the soi-disant 'good' cholesterol have only been demonstrated in clinical trials with medication, through surgical interventions, or through studies involving increasing consumption of certain specific foodstuffs – but as yet, no study has been carried out focusing on changing the patient's diet completely..

“We compared two types of Mediterranean diet: one rich in olive oil and the other rich in nuts; both within the context of a low-fat diet,” says the research team.

“We saw that adhering to a traditional Mediterranean diet, especially one rich in olive oil, was associated with a significant improvement in HDL functions.”

Research group coordinator Montse Fitó – who is also part of the team at the Biomedical Research Centre's Obesity and Nutrition Physio-pathology Network (CIBEROBN) – says numerous scientists have recently indicated that the biological functions of HDLs are those which best explain the cardiovascular protection element of 'good' cholesterol.

She says this would explain why people with circulatory and heart conditions have worse-functioning HDLs than those with healthy cardiovascular systems.

The study involved extracting HDLs from blood samples before heart operations and a year after the patient had followed an exclusively Mediterranean diet.

The study, which opens the door to new forms of treatment being developed to improve HDL function and control and prevent cardiovascular conditions, has attracted the attention of the American Heart Association – the world's most prestigious heart and circulation health organisation.