Not what you think
Be sure you are using a high quality virgin (not extra virgin) olive oil that is stored in a dark bottle.
Other excellent oils include virgin coconut, palm oil (great source of vit E), avocado oil, macadamia nut oil. I do not recommend any vegetable oils (soybean, corn, etc), nor canola oil. My opinion is that HIGH OLEIC sunflower/safflower oil is fine.