I believe biggest sink for glucose are portions of brain that cannot use ketones for fuel. As to yeast -- that's right, that is exactly the point. Rather than

I believe biggest sink for glucose are portions of brain that cannot use ketones for fuel. As to yeast -- that's right, that is exactly the point. Rather than eat yeast extract which is basically proteins and nothing else, I would take a look at a small amounts of broth in daily diet. It is possibly safer (people can survive on broth alone so small dose of it daily shouldn't be a problem) and it tends to contain a lot of useful stuff for the organism. It is not strictly zero calorie diet but I think if your aim is health this is probably for the best rather than seeking ideal of zero calories.