For many years, the Mediterranean diet has been associated with better cardiovascular and metabolic health. Now a new study shows that olive oil can change the composition of blood metabolites and lower the risk of developing cardiovascular disease by 30%. Extra virgin olive oil appears to be especially health-promoting.
The food in the Mediterranean region is now well established to be associated with better cardiovascular and metabolic health – and a longer life.
The reason is all the healthy ingredients in fruit, vegetables, fresh fish and olive oil, the usual components of a traditional Mediterranean diet.
Now a new study shows that olive oil itself is associated with a healthier metabolic profile that considerably reduces the risk of developing cardiovascular disease and that the type of olive oil also matters.
“This study shows that you should replace the oil you use with a healthier oil because it is associated with better health. Extra virgin olive oil is especially associated with cardiovascular health benefits,” explains a researcher behind the study, Marta Guasch Ferré, Associate Professor, Section of Epidemiology, Department of Public Health, and Novo Nordisk Center for Basic Metabolic Research (CBMR) at University of Copenhagen, Denmark.
The research has been published in Cardiovascular Diabetology.
Well-known health benefits
According to Marta Guasch Ferré, research has gradually established that olive oil is healthy.
The health-promoting effect of consuming olive oil results from the content of vitamins and polyphenols, both of which are associated with better health.
This applies especially to virgin olive oil and extra virgin olive oil, both of which contain higher quantities of these healthy substances than regular olive oil and especially other types of vegetable oil.
However, how consuming olive oil affects the composition of several hundred metabolites in the blood (metabolome) has not been known.
Metabolites express the result of processes inside the body and can reveal details about health and disease. Some metabolites can even be used as markers for developing disease even before symptoms appear.
“This study therefore aimed to determine how olive oil affects the metabolome, the risk of developing cardiovascular disease and the risk of developing type 2 diabetes,” says Marta Guasch Ferré.
Comparing types of olive oil
The researchers analysed blood samples from a large study that examined how a Mediterranean diet affects people’s cardiovascular risk profile.
The original study involved nearly 7,000 people randomised to eat a Mediterranean diet plus olive oil, a Mediterranean diet plus nuts or a diet recommended 10 years ago by the American Heart Association.
All participants already had a high risk of developing cardiovascular disease, including having type 2 diabetes, elevated cholesterol or a family history of cardiovascular disease or smoking.
The results showed that the Mediterranean diet was associated with a lower risk of developing cardiovascular disease than the diet recommended by the American Heart Association.
In the new study, the researchers analysed 1,837 of the participants’ blood samples at both baseline and after one year to determine the trends in the concentration of metabolites in the blood. They also investigated how consuming olive oil is associated with the risk of cardiovascular disease and the effect of the various types of olive oil.
30% lower risk of cardiovascular disease
The results show that consuming olive oil is associated with changes in the metabolome.
Virgin olive oil was associated with 78 changes in the metabolic signature, including changes in the concentrations of several lipids, acylcarnitines and amino acids, all of which are associated with good health.
Regular olive oil was associated with changes in only 17 metabolites.
The researchers also found that consuming extra virgin olive oil was associated with a 30% lower risk of developing cardiovascular disease within the follow-up period.
The reduction of risk applied to virgin and extra virgin olive oil but not regular olive oil.
The researchers also found no association with the risk of developing type 2 diabetes.
According to Marta Guasch Ferré, various factors may have created difficulty in finding statistically significant differences.
One reason could be that the participants received extra virgin olive oil for free, which might mean that too few participants consumed regular olive oil to make the results statistically significant.
“Further, the mechanism for developing type 2 diabetes could differ from that for developing cardiovascular disease. For example, healthy fat, such as that in olive oil, strongly affects cholesterol levels and therefore the risk of cardiovascular disease, which does not apply to type 2 diabetes,” explains Marta Guasch Ferré.
Switch to a healthier oil
According to Marta Guasch Ferré, the study shows that replacing other types of oil with olive oil promotes cardiovascular health, especially for people at high risk of developing cardiovascular disease.
“The result might differ for other population groups, but the conclusion for this group of people with high cardiovascular risk is that switching to a healthier oil could benefit their health,” concludes Marta Guasch Ferré.