Fasting, autophagy, and fat supplementation


(Woody Dailey) #102

I realize this is a rat study but it’s still interesting. As I read it it may make
a big difference just what fatty acids are being burned during your fast. It
might be interesting doing a fat fast that used a lot of monounsaturated fat.

http://jn.nutrition.org/content/105/2/185.extract


(David Cumming) #103

thanks for this explanation - I’m having trouble understanding completely, but it seems like a sound explanation. It’s does seem counter intuitive to me since we evolved an ability to store energy as fat for later use but then we also evolved to have a limit on how much of that fat we could use when we weren’t eating and needed it. Maybe it’s just me, but that doesn’t seem like a very elegant design.
I suppose burning protein/muscle (because your fat doesn’t give you enough fuel) would make sense in order to lower your BMR but it would make it increasingly harder to score your next kill. But I guess our species made it so it must work somehow :slight_smile:


(Richard Morris) #104

Yes limiting energy access to just 1% per day may sound like a poor evolutionary strategy, but it does mean that you have 3 months of energy. Maybe that’s the survival benefit. You can’t use all of it immediately.

It does seem that left to it’s own devices our bodies don’t appear to optimize for leanness but some adequate comfortable amount of body fat - I mean in the absence of a derangement due to modern sugars and starches.


(Gabe “No Dogma, Only Science Please!” ) #105

Very interesting thread, especially the link someone provided to Steve Phinney’s comments about fasting. It sounds to me as if fasts of <=48 hours are fine per Phinney; beyond that, he doesn’t approve.

Can anyone confirm that that’s their understanding?


(Chris W) #106

I’ve seen one of the presentations that Dr. Phinney speaks about fasting and yes, he seems to draw the line at about 48 hours as the limit of fasting that he can support with reservations. His primary concern seems to be with older patients since any loss of lean body mass is so difficult to rebuild as you get older.


(Gabe “No Dogma, Only Science Please!” ) #107

So basically what you’re telling me is I should start lifting while I’m still under age 40?


(Chris W) #108

I wouldn’t necessarily put a number to the age. Dr Phinney was likely been referring to patients in general and perhaps the generalization that many older patients may be less inclined to take up lifting or high intensity activity of any sort. After losing some LBM, which I believe was due to dropping protein too low for a while, I was able to restore it by increasing my protein a bit and stepping up my resistance and interval training a bit, and I am 52.


(Ty Belshe) #109

Here is a very recent video on autophagy from an expert in the field, Dr. Guido Kroemer, being interviewed by Dr. Rhonda Patrick:


It seems in humans it may take around 3 days of fasting to kickstart the process of autophagy and it’s unknown wether fat intake works against the process, a lot of people speculate it doesn’t however we don’t know definitively.


(G. Andrew Duthie) #110

Just watched that the other day. Good video, and I really like the way they provide on-screen definitions of many of the terms used. Wish that more health/science videos did the same. Would make the material more approachable for a wider audience.


(Robert) #111

I’ve listed to her podcasts and watched them and completely agree that the video’s are nice with the definitions/references to studies that she provides! If you’ve watched/listened to a few of her more recent podcasts, she does seem to be striving to determine the period after which autophagy benefits begin.


#112

Does this time frame take into consideration whether one starts a fast already keto adapted? This would be an interesting and useful parameter to know.


(G. Andrew Duthie) #113

I think the simple answer is…we don’t know.

Given what we do know, it probably varies from person to person. But even that is speculation.


#114

Thanks. So true about so much of this WOE.


(Doug) #115

This is such an excellent thread. I’ve read through it twice, and will need to do so again in the future. Some questions answered, others raised. There is so much to try and understand.


(Ty Belshe) #116

I’m going to have to agree with @BillJay after looking more into Dr. Valter Longo’s Fasting Mimicking Diet (FMD) it appears that autophagy does happen on a continuum. With the suppression of IGF-1 and mTOR, autophagy appears to ramp up. I believe the effects can start to be seen around day 3, but are very robust on day 5. Protien, especially leucine and methionine, will activate these pathways. Carbohydrates will activate these pathways to a lesser degree, though still substantial enough, as will beta-oxidation, but probably to a negligible effect. I believe I heard somewhere that the FMD suppresses the metabolic pathways around 80% that of water fasting. Dr. Longo’s team is looking more into the effects of his FMD and autophagy. In his patent the FMD looks like this:

 **Day 1:** 10 to 16 calories per kg bodyweight, 10% protein, 56% fat, 34% carbs
 **Days 2 – 5:** 7 to 11 calories per kg bodyweight, 9% protein, 44% fat, 47% carbs

Using myself for example (I weigh 140lbs, or 64kg), starting on Day 2, my total calories would be 450-700, with protein at 10g-15g, and carbs at 52g-82g.

To me, and I’m sure any keto-adapted person, the carb content seems high, but he’s getting outstanding results in animal and human clinical trials. I just completed a modified version of this, hoping it would be superior and more in line with being already keto-adapted. All 5 days I stayed below 10g of protein and 10g of carbs, which makes 80 calories, and I filled the rest of my calories in the range I mentioned above with fat. Both protein and carb macros were obtained from greens, avocado, nuts/seeds (salad contains amino acids and when you’re limited to 10g a day, the amount of protein from greens is significant); I ate no animal protein except one day I had an egg yolk…yum :slight_smile:

In response to @riportner, I believe (and this is purely speculative) that being already keto-adapted with lowered carbs and insulin will give a head start, but by how much? Probably not a whole lot but it does take carb-adapted people around 48 hours+ to get ketones even near that of keto-adapted individuals. I’m sure our head start into deeper ketosis for longer has a greater therapeutic effect in some way, but as far as autophagy goes, I think what matters more is the protein aspect, which is why I think, we don’t get that great a head start. I could be wrong, hopefully the science comes out soon, until then, happy experimenting.


(Sjur Gjøstein Karevoll) #117

If the main thing regulating autophagy is energy density in the cell then being keto adapted shouldn’t have much of an effect. If anything, a metabolism tuned to increased lipolysis would increase energy availability during a fast, decreasing autophagy. This is pure speculation on my part though.


(Richard Morris) #118

For a diet to be fasting mimicking but yet not a fast it would have to supply adequate glucose for the brain and other glucose dependent tissue … or it would have to be ketogenic which as you point out takes 2 days at a minimum to burn through glycogen. So he pretty much HAS to put about 100g of carbs in the product.


(Ty Belshe) #119

@richard I never really thought of it like that. The cool thing on top of that is that insulin is also dependent upon total calories, so because of the calorie deficit, ketone levels actually get pretty high on the fasting mimicking diet as per Dr. Valter Longo. So I guess it’s not so strenuous on the individuals who utilize FMD because they get to run on dual fuels and get the therapeutic benifit of ketosis.


(Saruul Khas) #120

I was looking for answers for the same question and found this blog :):+1:

I found this article.

Maybe answer is in there. It is hard to understand this kind of scientific paper for me :slight_smile:


(mike) #121

I have been interested in this topic for some time and decided to do some digging this evening. I did not have to go farther than entering “ketosis autophagy” into the search bar and got the below blog post, which included the article posted below it. Pretty cool info.

This one is by Dr Michael Eades.
https://proteinpower.com/drmike/2006/02/27/ketosis-cleans-our-cells/

http://www.jbc.org/content/280/27/25864.short