> you thought that cells only metabolize glucose, and dietary fats & proteins are converted to glucose
Pretty much. I don't know where that may have come from, but I suspect I'm not the only one who naively thinks that this is the case. Somehow "ketone bodies" aren't mentioned in dietary conversations nearly as frequently as glucose.
During very low carbohydrate intake, the regulated and controlled production of ketone bodies causes a harmless physiological state known as dietary ketosis. Ketone bodies flow from the liver to extra-hepatic tissues (e.g., brain) for use as a fuel; this spares glucose metabolism via a mechanism similar to the sparing of glucose by oxidation of fatty acids as an alternative fuel. In comparison with glucose, the ketone bodies are actually a very good respiratory fuel. Indeed, there is no clear requirement for dietary carbohydrates for human adults. [...] Contrary to popular belief, insulin is not needed for glucose uptake and utilization in man.
LOL yeah, I just spoke to a dietician the other day who swore that glucose is the only thing your brain can use for fuel.
It's easy to be ignorant about a situation you never experience. Every single person they deal with is going to be in a carb-adapted state and never miss a meal, so their body will run entirely off of glucose.
I vaguely remember reading about this in "The Ketogenic Diet". There are some functions that do require glucose. However, your body can convert enough fat and protein into glucose to satisfy that.
Yeah, that was a TIL moment for me when I found out the body can make glucose without carbohydrate. There were others, like how mitochondria burn fat more efficiently than glucose.
Can you expand? Like, you thought that cells only metabolize glucose, and dietary fats & proteins are converted to glucose? Or...?