The sort of food people are going for doesn’t even exist in the natural environment. Good luck finding so much refined sugar in one place or processed fat. Never mind the various preservatives that play the cognitive dissonance game of being a hostile environment for foreign microbiota but hopefully don’t do anything untoward to your own gut microbiota.

It isn’t just playing our systems, but hacking them and giving them inputs they would never usually see for far stronger effects than would be possible.