"Starting in June 1965, Scottish man Angus Barbieri (1939 – 7 September 1990) fasted for 382 days. He lived on tea, coffee, soda water and vitamins, living at home in Tayport, Scotland, and frequently visiting Maryfield Hospital for medical evaluation. He lost 276 pounds (125 kg) and set a record for the length of a fast."
I’m about to give up on total fasts and have bone broth a few times a day for the minerals.
Keen to know if we have learned more in this space
https://medlineplus.gov/ency/article/000394.htm
Magnesium and potasium main but not only function is to regulate heart beat. Lack of them might lead to arrhythmia and other complications.
Not sure about muscle loss.
If you supplement minerals and listen to you body response, then you can fast as long as you have fat stores in your body.
Its only dangerous if you don't know what you are doing or ignoring signals from your body. Lightheadedness is common thing people report or /r/fasting/ and almost always they don't take salt while fasting.
But I am not an expert, it feels like I have done more reading about fasting then actual fasting. So don't take advice from strangers (especially /r/fasting or worse dryfasting nutcases).
This is dangerous and please don't encourage others to do only water fast. Pure water fast is dangerous beyond 4 days or so.
You need to supplement minerals while on per-longed fast. Salt, magnesium and potassium are vital to regulatory processes in your body.
When your body uses up all reserves it will not be able to sustain those processes. It is serious business so please read up on the subject while trying anything longer than 3 days.
> feeling of dying and lying in bed shivering on a 5-7 day.
This is body telling you something is wrong, ignoring is outright stupid. Like ignoring that you are bleeding.
> I have fasted 100 lbs away Congratulations