I think the two ideas are that you are supplying more cholesterol and fats, which is the hormonal advantage.
IMO this is another erroneous theory made on the basis that if a deficiency in a particular nutrient leads to a deficiency in some metabolic process then a surplus in said nutrient will result in an extraordinary level of the same process. Other examples of this include chromium for blood sugar and protein for muscle growth.
An additional shortcoming of this theory is that carbs also have their advantages (fast burning fuel, micronutrient profile). By severly restricting them you are simply creating another deficiency.
The reality is that the body is primarily programmed for survival and consequently has 'governors' on most processes. If you want a hormonal advantage visit the steroid forum.
Also, the low amount of carbs prevent insulin spikes as you know, and also allow growth hormone to be increased.
Don't confuse insulin output for carbohydrate metabolism versus that for fat metabolism. What is an insulin spike anyway? 1 picomol/L? 10 picomol/L? Insulin management for non-diabetics is another bogus approach IMO. Sure its good to know that high calorie density, processed junk food messes with it but it is not readily quantifiable nor is it well understood. Energy intake on the other hand addresses the same problem and is quantifiable.
Your body prefers fat for fuel instead of carbs. This means you burn FFA's first. Even if both diets had equal calorie deficits, the higher carb diet would see you re-store those fats, when the deficet is presented again, your body will not use all fat for cals, it may tap into LBM. and glycogen before fat.. with CKD/TKD it is more likely to use fat over LBM.
I thought it was the reverse. Fat is a slow burning energy source; it cannot be used at high intensity activity levels. Glucose on the hand can be used at all levels.
Also, every time the body converts a macro to another (note this is one way only: protein -> carbs -> fats). It must used energy to do it. For the sake of efficiency (ie survival) the body will prefer to store carbs as glycogen. Fats since they cannot be converted backwards can only be stored as fat.
Anyhow, good debate - though I feel like this horse died a long time ago. Even if you don't buy all my arguments try and take away my point that most of these theories put forth by people (who btw usually stand to gain financially) usually only hold up to analysis when the context is sufficiently small. In the real world with all variables considered I think you're better off giving your body all the resources possible by eating a more balanced diet at an appropriate calorie level and letting your body manage itself.
