Fructose Metabolism

[ATP]

These two guys along with Lustig are the most prominent individuals that promote the anti-sugar sentiment.



View: https://www.youtube.com/watch?v=5jBsWbDGtWU



His theory on fructose metabolism

- The phosphorylation of fructose to fructose-1-phosphate by fructokinase significantly lowers ATP and intracellular phosphate concentrations.

- The rate at which ATP concentrations reduce is so fast that the cell is unable to regenerate ATP levels, AMP deaminase is activated which catalyses AMP to IMP and ultimately uric acid.

- The uric acid inhibits AMP-activated protein kinase, which coupled with the low AMP levels further halts the regeneration of ATP.

- The metabolism of fructose via fructokinase leads to many negative effects such as increased oxidative stress (NADPH oxidase), inhibition of aconitase (Krebs cycle) with an increase in glycolysis and lactate production.

Even though muscle and adipose tissue utilise hexokinase to metabolise fructose, other extrahepatic tissue such as the brain utilises fructokinase.

The body can also endogenously produce fructose from glucose (polyol pathway), he claims that there is no distinction between the negative effects of dietary fructose and endogenously synthesised fructose.

His theory is essentially the metabolism of fructose leads to mitochondrial dysfunction, reduced oxidative phosphorylation, and ultimately a low energy state.


What does everyone think about his claim about fructose?

 

[Eberhardt]

more discussion friendly maybe is if someone could point out the faults of his theory?!?

 

[Perry Staltic]

smh at people thinking eating fruit is bad.

 

[ATP]

It's specifically his claim that fructose activates AMP deaminase whilst inhibiting AMP-activated protein kinase and aconitase. Phosphorylation of fructose does initially utilise ATP as a cofactor but from glycolysis there is ultimately a gain in ATP. His theory essentially means that the nucleotide generation is inhibited from fructose.

 

[Cuki]

Richard Johnson has a patent pending on a fructose inhibitor. He's always bad mouthing fructose.

"metabolism of fructose leads to mitochondrial dysfunction"
So an extent, this is true, but only when UV falls away in the autumn. You'll need brand spanking new mitochondria for winter thermogenesis.
You're supposed to get a little mitochondrial dysfunction, it's by design.

 

[SamYo123]

smh at people thinking eating fruit is bad.

If fruit causes me beardruff and inflammed skin from the itch, than it is bad?

 

[Perry Staltic]

If fruit causes me beardruff and inflammed skin from the itch, than it is bad?

For you it may be. I was smh at people who think it is bad for health in general, like the doctor in the video.

 

[SamYo123]

For you it may be. I was smh at people who think it is bad for health in general, like the doctor in the video.

Ok, so why would it be bad? Whats causing it to be bad for those that get a negative reaction?

 

[Motorneuron]

By eliminating fruit I solved my candida problems and with starch my mitochondrial chain seems to work better ... or it's probably just a coincidence that I can't prove

 

[joaquin]

Maybe there is some context. @Cuki made some good points.
If I am carnivore for a few days, then eat some honey or some apples, I get a burst of energy and can do weights for muscle strength. If I continue too long at the honey and apples, my strength depletes and I feel lifeless. Something to be said for avoiding gluttony. To everything there is a season, and as cuki said, its by design. That is to say, God made everything and there is nothing that has no purpose.

 

[Peachy]

By eliminating fruit I solved my candida problems and with starch my mitochondrial chain seems to work better ... or it's probably just a coincidence that I can't prove

Did you continue eating starch while you were working through the Candida issues?

I was just thinking about fructose metabolism related to Candida this morning. I have a child who doesn’t eat fruit except in rare circumstances. My husband doesn’t gravitate toward it either. He much prefers starch and seems to tolerate it well. He eats some fruit because he knows “it’s good for him”. He’s been dealing with Candida issues and I’ve wondered which way he should go in working through them. My hunch was more sugar/fructose based carbs so reading your comment was interesting.

Both my child and husband have a similar constitution and I’ve wondered if they avoid fruit because something is amiss with their fructose metabolism or if that’s just their unique makeup. The rest of us are fruitiholics.