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0 pointscthalupa1mo ago0 comments

This is a bunch of pseudoscience.

"Starvation mode" as people talk about it is generally nonsense - the exceedingly low bodyfat you mention for keto is the same place you would see it in a non-keto diet when we talk about actual starvation mode and not whatever you're talking about with a non-ketogenic diet.

The only real difference when it comes to the biology here is that fat mobilization into glucose is significantly slower and less efficient, which keeps your blood sugar levels more constant, which results in fewer post-meal food cravings. Which isn't nothing, but it's not muscle sparing in and of itself.

We have plenty of studies here. Keto diets are not better for sparing lbm.

https://pubmed.ncbi.nlm.nih.gov/38934469/

In fact, if you already have significant muscle mass, it might be worse. Glycogen is hugely important when doing resistance training, and keto significantly impacts your glycogen stores. People perform worse with their resistance training on keto than regular diets.

https://pmc.ncbi.nlm.nih.gov/articles/PMC9244428/ https://pmc.ncbi.nlm.nih.gov/articles/PMC8469041/

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storus1mo ago

I suspect you have no idea that your body has two independent energetic circuits - one driven by insulin and glucose, the other driver by ketones. Just please dump this to any decent LLm to give you ELI5. Muscles obviously need glucose for their best performance which is why strength training is not recommended during ketosis; OTOH ketosis is naturally muscle-sparing.

cthalupaOP1mo ago

> I suspect you have no idea that your body has two independent energetic circuits - one driven by insulin and glucose, the other driver by ketones.

I am fully aware - I have spent several years of my life following a ketogenic diet. None of that is relevant for "starvation mode" and insulin within that context. I was replying to your specific points - not providing an explanation on how ketosis works from end to end.

Unless you are claiming that your body just doesn't produce glucose/glycogen and insulin when in ketosis? Which would also be incorrect.

> Muscles obviously need glucose for their best performance which is why strength training is not recommended during ketosis;

Strength training should 100% still be done in ketosis/while following a ketogenic diet. It will be suboptimal compared to a regular training, but being in ketosis doesn't magically make resistance training optional if you want to be healthy.

> OTOH ketosis is naturally muscle-sparing.

It is not and the study links in my post show consistent data here. There might be an exception if you are an endurance athlete but that is based on far more limited data than the rest of the research. So... if you're a high level endurance athlete that is also somehow fat, keto might be a better option when it comes to sparing muscle, but for the rest of us, not the case.

storus1mo ago

You keep mixing normal carbohydrate metabolism with functional starvation mode when in low caloric high carb diet, i.e. elevated insulin in a low-energy/tired mode with increased cortisol, ramping up gluconeogenesis from muscle tissue, catabolic state from elevated stress hormones, T3 thyroid hormone underproduction, adrenaline spikes leading to insulin resistance beta-andregenic sensitivity downregulation, none of which is present in ketosis from e.g. water fasting.

As for ketosis sparing muscles that comes from a wide range of effects like low insulin, preserved/increased GH/IGF-1, BHB-inhibited muscle proteolysis and low leucine oxidation.

https://pubmed.ncbi.nlm.nih.gov/41035089/

Your super confident attitude is likely going to lead nowhere for any people following your advice and when they confront you about not reaching any fat loss goals, your response will be likely "it's you", instead of understanding the gaps in your own knowledge.

cthalupaOP1mo ago

Your body doesn't enter starvation mode until you are in the 4-6% body fat range no matter what your diet is.

I linked 3 reviews/analysis of a large group of studies.

Your study also doesn't argue what you think it argues.

> A total of 33 studies were analyzed, revealing no significant differences between the KD and other diets in muscle mass

But fundamentally it is not a meta-analysis of people on weight-loss diets, it is a meta-analysis of people on keto. Look at the included studies - nearly half of them were on athletes. They weren't tried to lose weight - they were just eating keto. No one is saying that maintaining on keto is going to cause muscle loss.

Your confidence is the problem here - you're throwing around a bunch of words you don't understand and linking studies you didn't read.

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storus1mo ago

cthalupaOP1mo ago

> I suspect you have no idea that your body has two independent energetic circuits - one driven by insulin and glucose, the other driver by ketones.

Unless you are claiming that your body just doesn't produce glucose/glycogen and insulin when in ketosis? Which would also be incorrect.

> Muscles obviously need glucose for their best performance which is why strength training is not recommended during ketosis;

> OTOH ketosis is naturally muscle-sparing.

storus1mo ago

As for ketosis sparing muscles that comes from a wide range of effects like low insulin, preserved/increased GH/IGF-1, BHB-inhibited muscle proteolysis and low leucine oxidation.

https://pubmed.ncbi.nlm.nih.gov/41035089/

cthalupaOP1mo ago

Your body doesn't enter starvation mode until you are in the 4-6% body fat range no matter what your diet is.

I linked 3 reviews/analysis of a large group of studies.

Your study also doesn't argue what you think it argues.

> A total of 33 studies were analyzed, revealing no significant differences between the KD and other diets in muscle mass

Your confidence is the problem here - you're throwing around a bunch of words you don't understand and linking studies you didn't read.

j / k navigate · click thread line to collapse