you may not require carbs, but you certainly require glucose, and the body's ability to manufacture it from substrates does not come without added stress. not everyone's body adapts to gluconeogenesis equally well. this is where the word 'optimal' comes into play. it just aint optimal for everyone. what's the point of forcing yourself to deplete all glycogen. there's nothing particularly 'natural' about that.
Originally Posted by moonlights
also, everytime someone points out that you don't need to eat carbs to make glucose, i'd like to point out that you don't need to eat a single solitary drop of saturated fat to manufacture all the saturated fat you'll need. no essential carbs, no essential saturated fat, or monounsaturated fat either. essential only applies to the n6 and n3 fats, and denotes the fact that you can't make them. i dare you to eat a low-fat vegan diet and manage to avoid all n6 and n3. it won't happen.
"dean ornish and dr. davis think the palmitic acid our bodies use for fuel while we sleep is poison if we eat it. zero-carbers like charles washington think the oldest fuel in our evolutionary history – glucose - used by organisms a billion years ago and without which the brains of modern mammals cannot survive for more than a few minutes – is an unnatural toxin if you eat it. both views ignore basic facts of medical physiology and defy evolutionary history." - kurt harris