From Susan Thixton of www.TruthAboutPetFood.com
"AAFCO has never defined human grade ingredients in pet food. So without a definition, the claim is not allowed per AAFCO. This lack of a AAFCO or state law definition of human grade ingredients in pet food is what led to the lawsuit that Honest Kitchen pursued. The state of Ohio said ‘there’s no definition of human grade ingredients, so you can’t have that on your label’. This pet food took the issue to court, and successfully proved to the court and FDA each and every ingredient in their pet food was human edible. In turn FDA gave this company their ‘No Objection’ to the human grade claim.
FDA ‘no objection’ overruled state law and the human grade claim was allowed. AAFCO remains firmly in the Stone Ages believing that all pet foods are feed grade (actually AAFCO uses the term inedible – food is edible, feed is inedible) – and they have adamantly refused to step into the future and define this classification of pet food ingredient quality. At the next AAFCO meeting (August 2015) they will be discussing this."