>>7299828You do not get to spread false information. Sorry, you just don't.
Fructose gets phosphorylated when it gets into the cell to start glycolysis among other things.
Glucose becomes fructose at the start of glycolysis. This is BASIC biochemistry.
You can NOT convert protein into sugars. Proteins are amino acids, they basically all come from the basic building block: glutamate (which comes from α-ketoglutarate from the citric acid cycle).
If you don't eat sugar your body can do proteolysis (metabolize muscle mass) or from the protein you've ingested to get energy, but the brain feeds on glucose, so you should basically just consume sugar for optimal brain function and no more than that.
Carbs are literally chained glucose molecules, called amylopectin and amylose, or more familiarly called: starch.
Fun fact: cellulose is also chained glucose, but has a different chemical bond, making it indigestible for humans (and very sturdy material)
