Why can you eat food indiscriminately, but you can't talk nonsense?

Hello, the main meaning of this sentence is that when you speak, you can't talk nonsense without knowing things, and you can't talk behind others' backs, because it is easy to hurt people and bring you trouble, just like the old saying goes, "disaster comes from the mouth"! It means you can eat whatever you want. People eat indiscriminately to support their stomachs or to eat bad stomachs. At most, it is a little more comfortable and better. Will not hurt others, will not cause trouble to others. I think this can answer your question.