Hey LST. Yes. I do a 3 or 4 day water fast each month. After 2 days (or sooner if you were low carb before the fast) you will be running on keytones rather than glucose. Lots of factors may make that untrue for a specific individual. But it’s generally accepted 2-3days.
My guess is this is what impacts the experience. I have noticed a slower come up and even a dulling / less energetic experience. I generally avoid spice until I’ve eaten a meal and several hours have passed.
I’ve heard blood glucose levels can impact psychedelics in general. Seems to align w our experiences of fasting.
Peace
"Blinded by their own sight, hearing, feeling, and knowing, they don't perceive the radiance of the source. If they could eliminate all conceptual thinking, this source would appear, like the sun rising through the empty sky and illuminating the whole universe." - Huang Po