Traditional diets in the Mediterranean area using lots of olive oil. This oil lowers the risk of heart disease because it helps maintain blood flow and clear blockages in the arteries. According to research from Spain.
"Mediterranean diet rich in olive oil improves the function of high-density lipoprotein or so-called HDL, the good cholesterol," said study leader Dr. Alvaro Hernaez of Hospital del Mar Medical Research Institute in Barcelona.
Mediterranean-type diet consists of vegetables and fruits are rich in antioxidants, as well as whole grains and olive oil. This diet also tend to use low-fat protein such as chicken or fish.
"Our hypothesis is that the antioxidants in these foods may be bound to HDL particles and protect them from various types of attacks," said Hernaez. "Because HDL is more protected, they can carry out its biological function more efficiently and therefore capable of removing cholesterol from arteries or cause relaxation of blood vessels for longer," he added.
High levels of low density lipoprotein (LDL) or bad cholesterol and fats called triglycerides are associated with increased risk of heart disease and blood vessels.
HDL or good cholesterol is associated with a lower risk of heart disease because it helps remove excess LDL from the bloodstream.
From recent studies it, Hernaez and colleagues examined data from 296 older adults at risk of heart disease and blood vessels that were randomly assigned three types of diet: a Mediterranean diet were given an additional one liter per week of extra virgin olive oil, Mediterranean diet with an additional 30 grams of nuts a day or a low-fat diet.
Study participants average age was 66 years and they are required to follow the diet for one year.
Only low-fat diet is associated with a decrease in LDL and total cholesterol. Once the research report will be published in the journal Circulation. None of the three types of diets that increase HDL levels significantly.
However, blood tests and lab showed HDL function better in the group given a Mediterranean diet with extra olive oil.
Limitations of this study including the fact that the three types of diets that are relatively healthy thus making it difficult to detect the difference of the results.
"Nevertheless, this discovery adds to evidence that HDL function may affect the risk of heart disease and blood vessels," says Daniel Rader of the University of Pennsylvania, Philadelphia in an editorial accompanying the study.
"We know the Mediterranean diet reduces the risk of heart disease, but we do not know exactly why. There may be more than one reason, and the study found a possible mechanism that the Mediterranean diet improves the function of HDL," he wrote.
Even without clear evidence to explain why the Mediterranean diet may be good for the heart, this diet is still reasonable.
"For those who are interested in reducing their risk of heart disease, the Mediterranean diet may still include best proven diet to reduce that risk. The majority of people who do not have a problem keseahatan should switch to a Mediterranean diet as heart-healthy diet," he added.