Have finished the local Pic&Nic festival at Trevi. During the quite bits I was reading Extra Virginity by Thomas Mueller about as he say the "sublime and scandalous world of olive oil".
One thing in it I found interesting was that an olive oil's oleacanthal properties give it it's pepperiness and bitteriness. It is these same properties that give it some of the same anti-inflammatory properties as ibuprofen.
High quality olive oil is defined by it's pepperiness and bitterness. So to benefit from an olive oil's health benefits then you need to buy a quality olive oil and not any old blend found cheap in a supermarket.