I know there are a lot of fad diets and then there is calorie counting as a more science based approach.
I myself do calorie counting and follow a strict diet in order to avoid overeating.
How do you eat all day, you follow a system?
If you consume oil then you are not following a whole food diet. Oil is a processed or refined ingredient, therefore not a whole food. Obviously, you (as in you personally) can eat whatever you please, but I choose to follow a WFPB diet as intended and that includes no refined ingredients like salt, sugar and pressed pills, or processed ingredients like vegetable oils and such.