Hello Jeff Novick,
I recently watched a course from Lee Crosby, RD, LD, from PCRM. She addressed keto diets, and reviewed how macromolecules are handled in the body. It was my impression that she said that excess carbohydrates were stored as fat, and excess proteins had their nitrogenous waste excreted, but other breakdown products of the proteins stored as fat. I am not sure if this is correct, based on what I learned from Dr. McDougall. It was my understanding that glucose in the body is used as fuel for the cells in the body, stored as glycogen, and excess is burned off as heat energy and non-exercise movements; and that excess proteins formed crystalline products in the body that needed to be effectively evacuated via the liver and kidneys. It was my understanding that fat from the diet was primarily the fat stored in adipose tissues, because it is effective for the body to store fat as fat, whereas it is an expensive process to turn glucose into fat. Based on the studies provided by Dr. McDougall, showing that people who consume more carbohydrate do not gain more body fat, and my own experience, I am not sure how carbohydrates and proteins in excess both add to body fat. Perhaps I am missing something. It would help if you could clarify this for me. Thank you!