[me_me_me]

> I've gone as long as 12 days with nothing but water.

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

[hanche]

I remember reading about someone who fasted for an entire year. Of course he was morbidly obese when he started, he took supplements, and he was under strict medical supervision for the duration of the fast. (Sorry, don't remember the source.)

[guerby]

https://en.wikipedia.org/wiki/Angus_Barbieri%27s_fast

"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."

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2495396

[mrfusion]

I’ve yet to find a form of potassium that doesn’t upset my stomach when fasting. I’ve tried nu-salt, potassium citrate, and cream of tarter so far.

I’m about to give up on total fasts and have bone broth a few times a day for the minerals.

[beagle3]

potassium iodide might work for you.

[mrfusion]

Thanks. I’ll try it out.

[roystonvassey]

Interesting. Any studies that validate the first point? I recall research talking about how there’s little muscle wastage until day 21 in normal healthy adults.

Keen to know if we have learned more in this space

[PoachedSausage]

The figure I have seen is that muscle wasting drops to less than 0.2 kg per day once the body fully enter ketosis. Obviously, anyone considering a fast longer than a few days should do so under the supervision of a doctor who can monitor electrolyte levels etc. They can also check for the rare enzyme defect called Medium-chain acyl-CoA dehydrogenase deficiency, those with it are unable to fast safely.

[s1artibartfast]

Isn't 0.2 kg per day is a huge amount of muscle?? Thats half a pound a day!

[intotheabyss]

I know this is true just anecdotally. I'm totally ripped after a 7 day fast with none of my muscle wasting away, just the fat.

[me_me_me]

for salt look up topics around:

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.

[hourislate]

I agree, a 12 day fast is dangerous and unnecessary. I was experimenting and would never do it again. Anything longer than a 3 day fast (72 hours) is not necessary.

[me_me_me]

I didn't say that exactly.

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).