Society has been sold a bad bill of goods in terms of dietary fats from government agencies that know nothing about nutrition and don't care to. One is that dietary fat is bad and should be avoided. This is terrible advice because of how important fats are in the diet...good ones that is!
Most of the fat that people consume is polyunsaturated, highly processed oils that often times are rancid. These are nasty fats. But eating healthy fats like quality olive oil basically has no downside and the fats themselves are in perfect working order.
Add on top of that that they cause basically zero insulin response and this makes fats an excellent source of fuel. So they are great for diabetics.
Oh, and every cell in your body is composed of a fat membrane, so its sort of important for...well everything.
Olive oil is best used to douse salads and use directly on other foods. Bread for instance. Its hard to eat too much olive oil. That's the beauty.