Fasting, autophagy, and fat supplementation

(G. Andrew Duthie) #21

I don’t have the background to have an opinion, but I’d love to hear from @richard or @erdoke, who may, especially since I tend to include fat to make an extended fast manageable.

(Christina) #22

Right so I shouldn’t have hwc when fasting as my goal is not only to achieve autophagy but to burn my excess fat.


Ok…so what you have here is a hypothesis. You state “if I do x, I should achieve y”.

So, next step…test your hypothesis.

Develop a test plan…like…1 week using HWC in coffee…1 week no HWC in coffee. Compare data of both weeks. You may want to repeat the test, to see any crossover effects, so like week 3 with HWC and week 4 no HWC. You will have your answer in a months time and be in greater knowledge and control of your health.

This is the method I use. Seems a bit tedious…but, wow I have learned a lot using this scientific method process.

(Gabor Erdosi) #24

Nobody is talking about “plenty of fats”. On top of that, there are different goals and different conditions to start with. Lean people can reduce fat mass loss by carefully calculating their fat flow rate and estimating metabolic rate. The difference should be substituted with dietary fat. It might be zero for some people, 60 g for others and 120 for very lean, active folks.

(Christina) #25

Not tedious, thorough. I like it.

N=1 right? I’m going to test my hypothesis. :blush:

(G. Andrew Duthie) #26

Finally getting a chance to read through the post you linked. Some quotes/observations:

“Well so long that you’re throwing a few hundred calories of pure fat into your coffee, you will have less room to work with for your actual meals. What’s worse, butter/oil, on it’s own, does little to promote fullness.”

Granted, this is just my N=1, and based on my experience with extended, not intermittent, fasting (though I sometimes do BPC on IF), but I definitely find that adding fat makes for less hunger on a fast.

“So those calories are going to make maintaining a calorie deficit harder than ever before. Not to mention the fact that butter and oils are extremely low in vitamins and minerals, rendering them a terrible source of nutrition.”

Misunderstands both mechanism (seems to take the CICO attitude) and reasoning (not really looking to BPC for nutrients) behind the use of fat during a fast.

With respect to the section you originally quoted regarding the role of fat and suppression of growth hormone, and the follow-on difficulty in burning fat, I can only respond with my N=1 of having dropped around 4 pounds in 3 days on my current extended fast. Can’t prove that’s all fat, but I’m certain at least some of it is. Would I have lost more absent the fat in my coffee? Maybe. But I’m getting good enough results that if fat is what I need to make the extended fast tolerable, it seems like a reasonable trade-off.

I also take issue with the phrase “fat-only meal.” Adding fat to coffee isn’t a meal. It’s not meant to be. And for those of us who are fortunate enough to no longer have sufficient body fat to fully sustain our energy needs during a fast, that extra fat may actually be essential to avoid messing with our metabolic rate.

It’s certainly possible (perhaps even probably) that there are downsides to adding fat during a fast. But I am reluctant to accept a dogmatic statement that it should always be avoided. It is, however, good to understand the potential downsides when making the call on what works for you, so I appreciate you sharing the information.

(Sascha Heid) #27

I think people mean different things with fat-fast. For some its just a little bit of HWC or butter in their coffee, for others it’s 1500 calories of very fatty foods (like bacon) which has still considerably amounts of protein.
I dont have an opinion on what anybody should do, i just found it interesting to read about this influence on growth hormone, especially considering the low amount of research going on about fasting.
For me personally a little bit of very fatty food helps me to get through the day until my evening feast, but a 100% fat fast, even in unlimited quantities does not help me at all.

(Richard Morris) #28

Intermittent fasting can probably be accomplished without fat supplementation because there will be a reserve of energy circulating in lipoproteins.

The problem is with the 3 day extended fasts that people do to reach the threshold for maximum autophagy. If someone lacks the ability to produce enough energy from body fat to support their energy expenditure then they may have to supplement to avoid their metabolic rate dropping. This also stops the body scavenging for other energy substrates like protein - so eating fat could protect loss of lean body mass (in context).

Fat burning isn’t really a primary goal of extended fasting rather it’s autophagy, apoptosis, and chronic low insulin. But I accept that dietary fat is the primary driver of growth hormone inhibiting hormone, and that would indeed reduce the amount of fat burning.

(G. Andrew Duthie) #29

So, @richard, are you aware of any research that answers the question of whether autophagy can continue in the presence of fat supplementation during an extended fast? Because I would like to do 2-3 fasts a year specifically for the purpose of kick-starting autophagy and hopefully for cancer prevention. I may also want to do some fasts to burn fat, but as you note, those are separate goals, and from the standpoint of autophagy, I don’t really care if fat burning is inhibited.


Richards math, while being correct mathematically, misses the big picture. It has been shown that people can mobilize up to 1.5 grams per minute of fat (Volek) during endurance exercise once fat adapted. These athletes are already lean by anyone’s standards. that works out to a much greater amount than the 2005 study that used ancient data.

Using fat during a fast may make the undesirable effects of the fast more tolerable, but I doubt it can be successfully argued that it increases the effectiveness of the fast for weight correction or autophagy.

(Carol E. ) #31

Very true!

As I read and learned more about the fascinating topic of autophagy I made modifications for my fasting intervals of 24 hours or more.


My question would be, how many hours can they do that for without an external source of fuel? And are they fasted for several days before they begin?

(G. Andrew Duthie) #33

Not sure whether it can be argued successfully or not, but part of @richard’s point was that you probably shouldn’t lump those two goals (weight correction and autophagy) in together, since they may each require a different approach to maximize success with each.

(Richard Morris) #34

The FASTER study participants had a reservoir of lipids in circulating lipoproteins, not to mention lipid droplets already in muscle cells, and the meal they had just ingested in the process of being absorbed across their gut PLUS whatever energy they could coax from their fat cells. The 1.5 g/min figure is how fast lipids can be transported into mitochondria and oxidized from that pool.

Alpert 2005 was based on data from Ancel Keyes Minnesota starvation experiments, these participants were starved for 40 days and the only energy they had available was from body fat. The 290 kJ/kg Fat/day figure is the maximum rate that body fat can apparently release energy.

These are two different things.

(Richard Morris) #35

A small amount (short of stretching the stomach) of dietary fat should not affect glucagon mediated autophagy.

There are some contexts where NOT eating dietary fat could negatively impact weight correction. eg: if a person was unable to support their TDEE from body fat alone and did not supplement with dietary fat then their body would not only lower MBR but it would also seek other caloric substrates and may lose lean body mass in that process.


My multi has JUNK in it! I’m appalled and stopped it immediately!
Man…trying to be clean on the inside is confusing sometimes. Guess I’m back to JUST EAT REAL FOOD lol


Maria Emmerich claims any thing greater than 50 calories can break your fast. (30 Day Ketogenic Cleanse)

(G. Andrew Duthie) #38

The words “break your fast” don’t have sufficient meaning without the context of what your goal is.

Without that context, and without understanding what she says the consequences are of consuming more than 50 calories, it doesn’t tell us anything useful.

The only thing I found on her site was a comment to the effect of what you state, on this post:

I just don’t think that a comment on a blog post provides sufficient basis for making a decision one way or another on fasting and/or supplementing fat during a fast. It’s more complicated than that.


Yep…@devhammer provided me some good insight and suggested that there was potentially starch or something like that in the Centrum multivitamin. So, after a long time trying to find the ingredients on the web (very difficult…not explicitly on the Centrum website to consumers) I discovered (from Livestrong website) that the centrum multivitamins contain glucose and other fillers. I cannot comment on the validity of Livestrong site information…but, what I can say is that every time if took a multivitamin on my extended fast, I noticed a weightloss stall next day…it was repeated each time, never failed to observe that pattern.


Agreed. My bad to be rather vague. From her new book, page 54 in regards to bulletproof coffee in the morning in order to avoid eating until later in the day or to extend an IF,
"Consuming more than 40 to 50 calories takes you out of intermittent fasting…"
It stuck with me because I’m figuring out what works best for me and helps me fast for longer than 20 hours. I hadn’t tried fat to keep me going and it looks as if I had, it would have been enough to end the fast? I’m not sure if that is what she meant, but it’s how I read it.
Anyway, the comment I originally responded to pulled her words to the front of my brain.
“Using fat during a fast may make the undesirable effects of the fast more tolerable, but I doubt it can be successfully argued that it increases the effectiveness of the fast for weight correction or autophagy.”