Originally Posted by Donald Lee
Carbs blunt cortisol. If you're fasting, you can't get around it.
Fasting will also increase GH, which has a protein sparing effect. As long as you are still eating enough protein each day, I don't see this being a major concern for most people (of course there are exceptions for every rule such as people looking to go into bodybuilding or have an extremely high activity level...like athletes).