Extra-virgin olive oil may reverse insulin resistance: study

A compound commonly found in extra-virgin olive oil may reverse some of the negative effects of a high-fat diet such as insulin resistance and liver disease, a new study claims.
Hydroxytyrosol is a polyphenol found in extra-virgin olive oil, which is known to have antioxidant properties and may play a key role in its health benefits, researchers said.
Researchers from University of Chile fed four groups of 12-14 mice either a high-fat diet (HFD) - 60 per cent fat or a control diet - 10 per cent fat, with or without five milligramme hydroxytyrosol per kilogramme body weight for a 12 week period.

Blood and tissue samples were collected at the end of the experiment to study the dietary effects on oxidative stress, fatty acid composition and enzymatic activity in multiple organs.
Analysis of blood samples showed an increase in levels of total cholesterol and low-density lipoprotein (LDL) cholesterol with no change in high-density lipoproteins (HDL) cholesterol in mice who were fed a HFD, which were all attenuated by hydroxytyrosol.
HFD also increased markers of insulin resistance in the blood which were reduced by hydroxytyrosol, though not to the levels of mice fed a control diet, researchers said.

"Our results indicate that hydroxytyrosol may be a key part of the health benefits of extra virgin olive oil," said Rodrigo Valenzuela of University of Chile.

"We have demonstrated that this compound may offer protection against oxidative stress and detrimental fatty acid composition in the liver, heart and brain caused by a high-fat diet."
"Hydroxytyrosol is a polyphenol found in extra-virgin olive oil, which is known to have antioxidant properties and may play a key role in its health benefits," said Rodrigo Valenzuela of University of Chile.
The study was published in the journal Lipids in Health and Disease.