If you are accustomed to eating carbs, then you’re going to be primarily using glucose for energy. Now, say all of a sudden you replace the carbs with fat alongside your protein. Does this mean that the body will now primarily use the fat for energy, or (since you haven’t entered ketosis) will it preferentially resort to burning protein until it switches over to ketosis?
If your body is in need of fuel any form its going to use what you give it. If it needs glycogen and you dont feed it carbs it will take/make it from protein/aminos you ingest, if you dont ingest carbs or aminos it will use liver stores then go to muscle’
simple version but hope it helps
…If I remember correctly the bodies energy source goes…
if your no longer eating carbs, it will look for fats and proteins. It will also burn more fats then it did when you were eating carbs, however, this effect is negated if you are ingesting much more fat.
The body in general wants to use protein the least.
Don’t know if that answers your question.