I know of a few people who've done um long-term fasts, so three or four days with just water and electrolytes, maybe some ketones, and they were very overweight, carrying a lot of excess body fat, and when they returned to eating, claimed that their appetite was forever changed, in particular, the types of foods they were hungry for. And um that's thought to be uh an effect on the gut microbiome, which then impacts the brain.