I suspect that any oil will work for OP, as I suspect that oil kills bacteria. I'd like to know if anyone has tried hydrogenated cooking oil for OP or knows of anyone who has and what results there were. I certainly wouldn't swallow such oil after doing the OP, since it's likely a major cause of heart attacks and strokes, since there was very little cardiovascular disease before the introduction of such oils and transfats in the 1930s. I don't hesitate to swallow good oils after doing OP.