20% calories from protein is very mainstream advice because of gluconeogenesis. The human body cannot store excess dietary protein in the form of protein ie more than what is needed every day. The average protein requirement is around say 1 gram per kg for simplicity sake. The excess you eat is converted by your liver to glucose....and then what you cannot burn of that glucose is then stored as fat! So its shortsighted to eat more protein than your requirements and satiation. If you need more protein to stay full then you will need to swap out some of your carbs instead. Because thats what the protein excess will end up as in your body after 4 to 6 hours.
So, when I eat excess protein would it show up as an elevated blood glucose level the next morning?
Stavia - Also, I usually completely avoid sugar and am careful not to overeat. Last night I went out to dinner to with friends and loosened my diet. I had two bites of my husbands sweet dessert and this morning my blood glucose was 116. Is my overall insulin resistance really better if just two bites of something sweet can put me in pre-diabetes territory the next morning? It seems that as long as I don't have any sugar my blood glucose is normal, but that my body hasn't gotten any better at processing sugar when I do eat it. Can pre-diabetes really be reversed? ... Or, just controlled?