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Comment by text70 | Hacker News Reader

I am having trouble agreeing with the statement that "...your body will convert the protein to glucose..."

Could you elaborate on that logic?

This[0] is a good starting point. Dietary protein can readily be converted to glucose in the body and either stored as fat or used as energy.

[0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3636610/

The article says in multiple places that in practice, little of the protein was converted to glucose.

Yes, my understanding is that it will only convert as much as it needs to support the parts of the body that actually require glucose to run.

Ah, ok. I think I figured out where my confusion was at regarding the catabolic pathways from both gluconeogenic and ketogenic amino acids. The correction looks something like [Keto-Acids[Ketone bodies]]

While most catabolic products are categorically and chemically ketones, the list of ketone bodies mostly falls within the list of Keto-Acids. All of which can get passed to TCA at some point, which in turn can feed into gluconeogenesis if the reaction pathway energy is favorable.

While several people refer to gluconeogenesis, to the best of my knowledge we _can_ make glucose from protein, but rarely do in practice. I have yet to see anyone convincingly show that we do.

Also check out diet doctors take on it which refers to actual studies. "Does protein adversely affect blood sugar?" https://www.dietdoctor.com/low-carb/protein

Anyone on a zero/near zero carb diet should be proof enough. We can't survive with _no_ glucose.

This is so so true but so many people don’t believe this is possible. I wish there was a way to formally study this. Once my children are out of the house, I’m going 0 carb. I’m already pretty close to carnivore.

This is a very well understood pathway in biochemistry called gluconeonesis. https://en.wikipedia.org/wiki/Gluconeogenesis

A few parts of your body can't operate on ketones, so there's a backup mechanism to produce glucose from protein (from muscle breakdown, if necessary) called gluconeogenesis.

However, There's no evidence I've see that gluconeogenesis can kick you out of ketosis. As far as I know, gluconeogensis is demand-driven, not supply-driven, so there won't be any extra glucose running around for your ketone-consuming cells to use, regardless of your protein intake.

Disclaimer: I'm not a nutritionist or biologist.

"The production of glucose from glucogenic amino acids involves these amino acids being converted to alpha keto acids and then to glucose, with both processes occurring in the liver. This mechanism predominates during catabolysis, rising as fasting and starvation increase in severity."

https://en.wikipedia.org/wiki/Glucogenic_amino_acid

The body can use protein to make glucose, it only will switch into that mode under low carbohydrate conditions like fasting or very low carb diets. It's less energy efficient of a pathway though.

gluconeogenesis

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