Food entering the body is not the ultimate source of moral defilement.

¹⁸And he saith unto them, Are ye so without understanding also? Do ye not perceive, that whatsoever thing from without entereth into the man, it cannot defile him;

¹⁹Because it entereth not into his heart, but into the belly, and goeth out into the draught, purging all meats?

¹⁷Do not ye yet understand, that whatsoever entereth in at the mouth goeth into the belly, and is cast out into the draught?