Yes…your body turns to burning body fat for energy versus burning glucose from your food. You can’t burn both simultaneously and your body wants to burn glucose first.Good news, it's not just your belief, it's been proven. A high protein, caloric deficit diet, has been proven to maintain lean muscle mass while still decreasing body fat.
(Power athlete radio ep. 649 for some good info on it)
However…once you’ve reduced your body fat down to your “ideal” level (sex, age, fitness level dependent), you don’t want to maintain zero/extremely low carb diet for long term.
Your body will produce cortisol to turn fat to energy. Long term elevated cortisol levels increase inflammation as well as breaks down muscle, bone and brain tissue.
So once you’ve eliminated excess body fat and restored metabolic flexibility, it is best to reintroduce healthy carbs.
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