Burn glucose vs burn fat

(Marius the butter craving dude) #1

Why dose the medical community consider that our primary fuel is carbs/glucose; and mention ketons only as an emergency one or a secondary. Why is the accepted primary fuel source harmful… I mean if it the primary foul source it should do good. Dose the distinction primary and secondary/emergency between sugar burning and fat burning is a correct interpretation ?

Why do we have sugar burning for then ? I feel like sugar burning mode is actually the secondary metabolic state, not the primary. Yet our modern diet is abundant in carbs and we grow up to be full time sugar burners.

(squirrel-kissing paper tamer) #2

This makes more sense to me as well. I’m still learning and reading though. Good questions!

(Mike W.) #3

Your brain runs on glucose no matter what metabolic state you’re in.

(Marius the butter craving dude) #4

Yes, but we can produce our own glucose from proteins in the liver.
Question is what is the body’s preferred/optimal state: burn fat and create it’s own glucose or burn glucose for all organs. ? And I am on the keto side. Keto for me did wonders.

(Mike W.) #5

I got you. I think it prefers to burn fat. It’s a more efficient fuel

#6

Do you know what percentage of glucose (vs ketones) is required by the brain? I think many brain cells use ketones preferentially, but there are some kinds that need glucose.

(Marius the butter craving dude) #7

Still my dilemma is what is the proper function and purpose of carb metabolism… Why the mainstream view glucose as the recommended fuel source for humans.

(Jane) #8

Follow the money when it comes to “mainstream views”. Carbs are cheap to produce, most have long shelf life and profitable.

(Carl Keller) #9

Why? Availability of carbs and the support of the AMA and ADA who say a diet high in carbs and low in fats is (falsely) deemed the healthiest. Most doctors are taught very little about nutrition and they just memorize what they are briefly taught.

Prior to the 60s, people primarily lived off of whole foods… lots of fats, meat, veggies and mostly unprocessed foods. Obesity, diabetes and heart disease was not that much of a problem, even though excessive smoking was a common thing. Enter big food and the explosion of refined foods and more specifically, processed sugar… in conjunction with biased studies and biased recommendations that said “Fat will make you die younger”. It’s all a recipe for the epidemic health problems we see today.

This paradigm is like the difference between cars that run on gas and cars that run on electricity. Fueling stations for gas driven cars are everywhere so it’s the recommended and most discussed fuel, even though electric cars are more efficient.

(Adam Kirby) #10

The second part is the easy one to answer: because the mainstream view is dumb as a bag of hammers and predicated on ignorance and junk science.

If your ancestors came from northern hunter-gatherers, you weren’t getting any kind of carb sources for most of the year.

(Randy) #11

$$$$$$$$$$$$$$$$

#12

I don’t have my books with me on vacation, but I recall reading somewhere that they think nutritionists got “the body prioritizes burning glucose” mixed up with “the body prefers burning glucose.” The body needs to get glucose converted to glycogen quickly, and since it will prioritize that ahead of burning ketones, people assumed our bodies preferred burning glucose. And then as others said, subsides given to sugar, corn, and wheat means the authorities that be have no impeding incentive to go back and look at the data.

(The o-chem police are coming) #13

I really don’t think the body has primary, secondary etc metabolic states, it will simply adapt to what’s available. It’s frigging amazing. As for glucose as a primary or secondary energy source, I thinks that’s largely historic and represents how we learned about biochemistry, glycolysis and the Krebs cycle. I think the body burns glucose when it’s available since it cannot be stored in a significant amount. And the body tries very hard to keep glucose levels in a narrow range to avoid serious immediate consequences. So it has to be burned or converted. Fats can just as easily be stored as burned at any time. So yeah, if there’s glucose around then your body puts glucose on the menu and turns on the whole endocrine, neurohumoral package that comes with it. If it’s not around then your body gets along just fine🤓. Seeing as it is actually far, far more complicated than any of us can possibly know, I think it’s better to be overly simplistic.

(Ken) #14

One big difference is the the body’s ability to make and store glycogen from glucose. It’s essentially a short term process that does not have a counterpart when eating fat. It’s very much an evolutionary survival mechanism, enabling the body to create fat with excess carbohydrate. That’s why understanding the role of glycogen in both lipolysis and lipogenesis is so important. You have to deplete glycogen to burn stored body fat, and you have to overcompensate it to create fat.

That’s why the occasional or periodic carb intake does not result in fat storage.

(Nicole) #15

The brain’s glucose usage will fall off as one becomes fat adapted (as I understand it). I often see the ~130g of glucose a day for the brain number, but I’ve heard that it can drop off to about 50g within a few months.

Someone correct me if I’m wrong. :slight_smile:

The only obligate glucose burner is red blood cells. Everything else can use fat or ketones. Like others said, clearing glucose is a priority but I have seen something that showed the brain will use ketones more once fat adapted even if glucose is an option. It makes sense that the body uses/prefers whatever fuel it is used to having. Plus if the brain really just wanted glucose, I’m sure the liver would have ramped up gluconeogenesis.

Just guessing though.

(Kim) #16

I think fat burning is preferred. If we compare ourselves to other animals. They eat while they have food, then they dont eat for several days and some hibernate, living off of their fat. If i imagine hunter/gatherer in the old times, im sure they ate a lot of meat when they had it, so it would not go bad they had to eat their fill. There were no refrigerators back then. There were times they didnt have anyfood much, as in winter. I dont pucture them baking cakes, having ice cream, or other high carb foods. Maybe some grasses, but mostly what vegetation amd meat the land had to offer.

So i believe we were designed to use keytones. It was only since the introduction and mass production at reasonable prices that humans became highly carb eaters. And since that time, we failed to use the fat we have stored and became super puff marshmellows.

Thats just my opinion based on reasoning though. I have no research to back this up.

(Empress of the Unexpected) #17

I’ve just been reading that there is a part of the brain that needs about 30 grams of glucose a day but that will be supplied by the liver if need be. 75 percent of the brain can use ketones.

(Running from stupidity) #18

That’s correct. Of course, some people have achieved a superb level of efficiency and their brains use no fuel at all.

(Mike W.) #19

:rofl:

(Empress of the Unexpected) #20

Do you stay up all night practicing this??