Ezekiel 4:10

And thy meat which thou shalt eat, the food which he should consume according to this strict rationing, shall be by weight, twenty shekels a day, estimated at some twenty ounces avoirdupois, about half as much as the average man needs for his daily sustenance; from time to time shalt thou eat it, not according to the demands of hunger, but according to the rations provided for, that is, at long intervals, very sparingly.