Albert Barnes Commentary Leviticus 21:6

"They shall be holy unto their God, and not profane the name of their God; for the offerings of Jehovah made by fire, the bread of their God, they do offer: therefore they shall be holy." — Leviticus 21:6 (ASV)

The word here and in (Leviticus 21:8) rendered bread, is the same as that rendered food in (Leviticus 3:11), (Leviticus 3:16), etc., and meat in (Leviticus 22:11). The reader of the English Bible should keep in mind that bread, meat, and food, were nearly equivalent terms when our translation was made, and represent no distinctions that exist in the Hebrew.