Originally Posted by MtnRide
Hey, do you have a source for this? I'm honestly curious as this isn't an area I'm that familiar with. A quick scan at scholar.google seems to suggest that ~5% of your energy comes from metabolizing protein.
It's tough to find a source because it's 100% wrong. Protein that's not used for building muscle, etc. is burned as fuel or used to make glycogen. Plenty of references on protein metabolism out there to confirm that. That's why there are so many "clueless" people who will tell you that 1g of protein = 4 kcal, just like 1g of carbohydrate, but because it's diverted to other places first it's not as available as carbs.
But what do they know?