Many people have pondered this question! Rest assured. It is ok to use olive oil for cooking. It owes its good reputation to its monounsaturated fatty acids. The type of fat found in olive oil lowers “bad cholesterol” levels (LDL), while protecting “good cholesterol” levels (HDL) and this reduces the risk of cardiovascular disease. Heat does not alter this property. Extra virgin olive oil also contains vitamin E and other antioxidants.
It is true that these substances are destroyed at very high temperatures, when oil is refined or fried repeatedly. However, it holds up relatively well in baking pans in the oven. Extra virgin olive oil also gives food an incomparable flavour. It is better to use a refined olive oil (simply called “olive oil”, with no mention of “virgin” or “extra virgin”) when frying. It tolerates heat up to about 220 °C (425 °F), while extra virgin olive oil smokes at less than 200 °C (400 °F). It’s not worth paying for an expensive olive oil if you plan to use it only during high-temperature cooking. Canola oil can also be used for grilling or a stir-fry. So, if you’re like me and like the taste, use olive oil for cooking.