[masraum]

I did it quite a bit for a year or two before Covid hit. I was doing a minimum of 24 hours and a max of 60 hours. Usually it was 36 or 48 hours. It's great, I didn't feel hungry (until the 3rd day, and that was mental, I'm sure). Each day of fasting you should lose about .75# (on average). Some folks will lose more, I think especially if they are active or heavier. I trained to run a 10k while fasting and to ride in an MS150.
Then when I was working from home during covid, I pretty much stopped. It was next to impossible with the wife and grandsons around and eating, and the stress didn't help.
About 2-3 weeks ago, I did an almost 56 hour fast. It was probably the second or maybe third time since Covid hit. I have a vague recollection of a 1 day fast, and may have done another.
I'm hoping to get started again.

When I started, my BMI was ~25.3, and I got down to 23.7.

This guy has a ton of info on fasting. Dr Jason Fung, he's written several books. He's an endocrinologist, I think, and has several clinics that mostly treat obesity and diabetes.
https://blog.thefastingmethod.com/fasting-a-history-part-i/
If you follow ^those^ blog entries, you'll eventually get through to page 29
https://blog.thefastingmethod.com/fasting-ghrelin-fasting-29/
He's got a lot of great info in those pages. I suspect it's probably most of one of his books.