I was reading over the Wikipedia page on ketosis.
“Glucose must be conserved in the fasting state because parts of the brain, retina, kidney and red blood cells depend exclusively on it for energy, and in order to conserve muscle protein which must be catabolized to provide the glucogenic amino acid substrate for synthesis of glucose.”
First, the easy question - if ketosis is maintained without fasting (that is, with an extremely restricted carb diet), the protein required to synthesize glucose can come from dietary protein, and not from muscle protein, right? That is…does breaking down muscle protein only occur during starvation?
“But after several days of starvation, the brain transitions to burning ketones in order to more directly utilize the energy from the fat stores that are being depended upon, and to reserve the glucose only for its absolute needs, thus slowing the depletion of the body’s protein store in the muscles.”
Secondly, are there negative health implications for the retina, brain, kidneys, etc. to operate on synthesized glucose for extended periods, either due to availability of glucose or other reasons?
And does the brain suffer any deficiencies by transitioning to burning ketones in order to save glucose?
The article also mentions a side effect of prolonged ketosis is “depleted glycogen stores”. Does that make sense? Ketosis only happens after glycogen stores are depleted - it’s a cause, rather than a side effect… or do I not understand?