We kind of do. The Okinawan diet is perhaps the best studied in the context of "Blue Zones" and they consume no olive oil. In fact, their traditional fat consumption is something like 6% of calories. Similarly, the Sardinians did not consume as much olive oil traditionally, as they do nowadays (56% up): https://ucdintegrativemedicine.com/2017/05/sardinia-centenarian-secrets/#gs.bcr052 I am not saying that substituting olive oil for vegetable oils or animal-derived fat is bad idea, but just ad