Fredrich Nietzsche said it’s all in the gut. He can even be read to mean that all view is the health of the gut. Soren Kierkegaard was all about anxiety.
I saw a scholarly book the other day that suggests that many saints and shamans who are or were associated with fasting and not eating actually had undiagnosed anorexia nervosa.
The effects of various envornmental factors (food, body, bacteria, society, etc ) seems to evidence a neasessary separation of the things of effect and our thoughts about them. While what is sometimes dialectical actually relies upon an incorporation of two distinct elements in a non-causal relationship.