metabolism
Autophagy
A cellular recycling process in which damaged components are broken down — upregulated by fasting and exercise.
Autophagy (self-eating) is the cellular housekeeping system that degrades and recycles damaged organelles. It is upregulated by fasting, calorie restriction, and high-intensity exercise, and is implicated in longevity research. Most of the mechanistic work is in animals; strong human fat-loss claims tied to autophagy are often over-stated.