Maximizing Autophagy

 

So Dr Jason Fung was asked the question:  Is there a time over which you should fast to maximize authophagy?  (In this video jump to 9:36).

He answered, and I paraphrase, we don't really know, but I would guess 24 to 36 hours.  He also recommends occasional longer fasts.

I started to transcribe his answer and he went on and on and on, so you can watch the video, but this is his full answer, which I am posting because I spent the time to transcribe it.

Again, we don't know but I can guess, but we don't know. So if you look at what happens during fasting we know that you mostly use glycogen during the initial sort of 24 hours - it lasts roughly 24 hours. And then there's that period of gluconeogenesis from 24 to 36 hours.  So that's the period of time that my guess is that there's going to be the most sort of autophagy and so on because you're breaking down the proteins at that point for gluconeogenesis.  And again that's the whole sort of sticking point with a lot of people in fasting is that oh hey you're breaking down protein, you're going to burn your muscle at 24 to 36 hours sort of thing.  It's possible but I don't think the research on alternate daily fasting really bears that out.  However, I think that's actually a good thing because one you're taking down old protein and then because of growth hormone increases you're going to rebuild new proteins so I think it's actually not a breaking down process, I think it's actually a renewal process.  If you look only at the breakdown from 24 to 36 hours and you miss that sort of refeeding sort of burst activity then you're going to miss the whole picture, you're going to say, oh well you know you're just breaking it down, but you don't see the fact that it's actually balanced now. 

Keeping in mind that the body always works this way so if you look at bones for example, your bones are not static, there are osteoclasts and osteoblasts, so when you go through life, you actually have cells called osteoclasts which eat away at your bone and you might say oh wow that's terrible.  No, because when you eat away the bone it actually stimulates the osteoblasts to produce new bone.  But if you only look at one side of it you'd say whoa these cells are terrible, let's just murder all these normal osteoclasts.  It's like yeah you're going to have terrible brittle bones that's in fact what happened with some of the drugs that we use bisphosphonates we starting seeing really really brittle bones after like 10 years. It was because the bones might have more calcium but they're old and were not renewed. 

So the same thing happens - you get this 24 to 36 hour period of time where you are breaking down protein and it's not necessarily protein it's also connective tissue and all that and I think you know to me that makes the most sense.  And this is a pure guess so keep that in mind nobody actually knows.  That is my guess as the best place for this sort of autophagy to maximize itself.  So I would guess that if you are trying to maximize this sort of thing for whether you're trying to break down skin or connective tissue or alzheimer's disease where you have sort of excessive protein in the brain my guess is that it would be most beneficial to do these sort of 24 to 36 hour fasts and then once in a while like once every month once every couple of months do an extended fast.  And that the reason we do this so maybe I have done this for a few patients is that I don't know where the best sort of benefits lie so therefore I'm going to cover all my bases.  Do an occasional long fast with some of these alternate daily fasts 24 to 36 hour fasts to try to focus in on this sort of protein breaking down period of time.  And when you do these 24 to 36 hour fasts, there's no coffee there's no anything but water and salt, right.  That's for the autophagy people.  I means there's a few specific people who come to us and they say and we're like ok you know to our knowledge this is going to be the best protocol for you but no you know somebody always goes oh have you proven this - like no, nobody's proven any of this but you can do it or you cannot do it it's up to you.