[SunkenCiv]

“Peasants ate bread that was so coarse it wore away their teeth”

The reason for tooth wear was that the grinding stones used left stone grit in the flour.

[maryz]

The reason for tooth wear was that the grinding stones used left stone grit in the flour.

Yes, I read something years ago that made that point -- written by someone impatient with the rhapsodies of stone-ground wheat enthusiasts: "Stone-ground wheat also contained a lot of wheat-ground stone."