It is well known that cows technically don't "eat" the grass, they actually "eat" the microorganisms living in their stomachs, hence why their feces are mostly grass. If cows "ate" the grass, the grass would be "gone". Because humans are obligate carnivores, when we eat steaks, we don't poop out a bunch of little steaks: what comes out is unrecognizable and very different from herbivores.
In the Framingham Offspring study, it was found that there was no difference in vitamin B12 levels between people who ate meat and people who didn't. The reason why that study showed no difference, it seems to me, would be because the demographics were most likely all eating a plant based diet, even while eating meat.
A typical "balanced meal", even for so called "meat eaters" (meat, veggies and bread etc) is still a plant based diet. The various demographics in the Framingham Offspring study were most likely all in glycolysis (as opposed to ketosis). In order to trigger ketosis, one must eat around 80% to 90% fatty protein for multiple days straight. Glycolysis, on the other hand, can trigger in a matter of hours. Given the ratios of modern diets of today, even the meat eaters participating in the study probably ate less than 50% meat, which would trigger chronic glycolysis.
In a paper about the Framingham Offspring study, it states:
"Oddly, the researchers found no association between plasma B12 levels and meat, poultry and fish intake, even though these foods supply the bulk of B12 in the diet. "It is not because people aren't eating enough meat," Tucker said. "The vitamin isn't getting absorbed."
How does that Offspring study handle chronic glycolysis in the design? Wouldn't chronic glycolysis interfere with the proper absorption of B12, and, wouldn't that be a plausible realm of exploration given the "odd" nature of the results?
Sugars from glycolysis directly affect available B12 in the blood which could shed light on the odd nature of the results from the Framingham study, in the participants who ate meat while still being B12 deficient. Sugar depletes B12. "Meat eaters" with B12 deficiencies are most likely in chronic glycolysis (that's a big part of the reason why they're deficient).
It is well known in the medical literature that chronic glycolysis leads to aging and neurodegenerative disorders because these types of brain disorders and accelerated aging, in general, all have a lot to do with B12 deficiency.
Chronic glycolysis usually accompanies insulin resistance and that can be very dangerous to our health. For these reasons above, our insulin response to macronutrients graph becomes an indispensable learning tool. Because insulin resistance can be so disastrous to our health, this graph could actually represent the ideal human diet, but only if we invert the ratios!
In the medical literature, the western mindset remains totally confounded by the nature of glycolysis. Too much and too little both seem to have the same effect on the body, subtly indicating that only 5% to 10% dietary carbs are optimal, in support of the insulin response graph ratio inversion!
Importance of the insulin response graph cannot be understated. Because the insulin response graph hints at the optimal human diet, I think it also hints at the optimal time periods humans should spend in either glycolysis or ketosis.
Again, when we invert the graph, in this position I have laid out, humans would theoretically be functioning optimally 80% to 90% of the time being in ketosis and 10% to 20% of the time being in glycolysis, that way both the metabolic stressors of glycolysis and ketosis would be effectively mitigated as they've been described in the medical literature.
It takes the human body nearly 5 days to enter ketosis, and yet only hours to enter glycolysis. Why? Because the metabolic pathways for glycolysis in the human body are not ideal!
The body will switch faster to glycolysis to properly handle the increased metabolic stress and increased metabolic waste generated from additional energy conversion processes involved in glycolysis/"carbtosis" with respect to fewer conversions happening in lipolysis/ketosis.
For example, glycolysis will only yield 10% to 40% ATP, while lipolysis will yield 60% to 90% ATP. The difference in ATP yield between glycolysis and lipolysis arises from the extra "work" undertaken in the glycolysis conversion pathways, meaning lipolysis is more efficient with less metabolic waste.
When we consider why too much chronic glycolysis and too little glycolysis have the same effect, the difference must have to do with the efficiency of the conversion pathways, as described by inverting the insulin response graph.
Theoretically, if the findings of the Framingham Offspring study were correct, and meat consumption had no bearing on levels of B12 in the population, the question would then be: would there be enough B12 sources available in a plant based diet? But then yet another question arises: what of the wild human, who did not originally plant food? Ah, but he was an apex predator, who never needed to tend a garden!