"At this point I will explain how bacon may be eaten to the best effect... if it has been simply roasted in the same way as a joint of meat, the fat drains into the fire and the bacon becomes dry, and whoever eats it is harmed and not benefited; it also produces bad humors and causes indigestion. But if bacon that has been boiled and cooled is eaten, it is more beneficial... As for raw bacon which, so I hear, the Franks have a habit of eating... they are healthier than other people because of this food. Let me give a good example so that what I am writing may be believed: thick bacon, placed for a long time on all wounds, be they external or internal or caused by a blow, both cleanses any putrefaction and aids healing. Look at what power there is in raw bacon, and see how the Franks heal what doctors try to cure with drugs or with potions."
Anthimus, On the Observance of Foods (c. 511-534)
From Ask The Past.
Previous posts: Mostly weird, and some not so weird, medical treatments from the old days, including this:
How to Stop Bleeding, 1664:
“To Stench a Bleeding Wound: Lay hogs Dung, hot from the Hog, to the Bleeding Wound.”
Samuel Strangehopes, A Book of Knowledge in Three Parts (166)
Advice from 1380: How to Tell if Someone Is or Is Not Dead, with bonus Monty Python.