I’d like to learn more about the mechanisms within the body during and after transition to fat burning. What is it that is not there when we are carb burners? What happens to those mechanisms when we reintroduce temporary carb sources?
Anyone already dove into this subject deeply have some resources to share?
Mechanisms of Carb to Fat Burning Transition
LindsaySue
#1
I’ll be back when I get a chance to read this. Thanks so much
PaulL
(You've tried everything else; why not try bacon?)
#4
The articles on the Virta Health site are very helpful. Many of them are by Dr. Phinney himself, and they go into such questions as you are asking.
Rclause
(Scott)
#5
I prefer to just call it magic. I could always get a keto war started on MFP with that.
LindsaySue
#7
Ok so these notes are really just for me, but I figured I’d post them since I wrote them in a comment.
This article really isn’t exactly talking about what I was asking about, but it was super interesting.
Unfortunately, I’m not quite knowledgeable enough to read this fluently, there are many words I don’t understand and many other words I don’t understand their use within the context. I’ll have to read this a couple times
The first thing that stood out to me was this:
“Much of the attention around metabolic flexibility is because of its implication in insulin resistance, a concept first advanced by Wilhelm falta and published in Vienna in 1931 as a possible underlying cause of type 2 diabetes.”
Just the fact that this has been KNOWN for so long, it’s criminal absolutely criminal that the average person, not to mention so many DOCTORS, don’t know about it.
My doctor is pretty cool but she still didn’t advise me to get an insulin test at my yearly physical last year because my insurance wouldn’t likely pay for it. I thought insurance companies were pretty good at wanting to be efficient with their use of funds–isn’t that why they cover yearly physicals for free because it will save them money on the long run? Why don’t they want to catch insulin resistance 20 YEARS before diabetes is diagnosed. UGH
Anyway moving on.
I found this concept intriguing:
“There is some debate about whether insulin resistance in muscle is a primary defect or an adaptation in diabetes…from the cellular perspective, excess glucose entering and stored in the muscle cell in the absence of increased energy expenditure could be harmful. Is insulin resistance than an adaptive response?”
The main point of this article is really about the body’s ability to use both glucose and fatty acids for energy under different circumstances, and particularly they are interested in exercises effects.
I definitely didn’t like being tricked into reading something telling me that I should really be exercising. I try to avoid all information to that effect. Darn it.
I did not know that “endurance trained athletes who have a high oxidative capacity in muscle can increase fatty acid oxidation in response to lipid overload, but they preserve glycogen storage within muscle at the expense of decreasing glucose oxidation”
I thought even athletes would have to use up all their glycogen before switching to fat burning. Not that I’m at any risk of being mistaken for an endurance athlete. That’s fascinating stuff. I’m assuming lipid overload means eating a lot of fat.
Anyway yeah they really don’t get into exactly what I was looking for, unless I’m not quite smart enough to read between the lines and figure it out. Which is entirely possible. Thanks for looking this up and sharing.
PaulL
(You've tried everything else; why not try bacon?)
#8
It makes sense that a fat-adapted athlete would burn fat for endurance activity, thus saving glucose to power explosive effort when necessary. Running down an antelope over a couple of days is one thing, but at the end, you may have to sprint forward to get good aim with your spear.
It really looks to me as though, evolutionarily speaking, fat should be the primary fuel, with the ability to deal with glucose as a safety mechanism to prevent hyperglycemia. In late summer/early fall, there would be an adaptative advantage to being able to store glucose in the fat cells, so as to build up a reserve for getting through the winter. Although this view may be a little to Europocentric to be really valid. Most of our evolution would have been in Africa, and I really don’t know the climate there.