Check writings by Valter Longo. The two principles are autophagy during the fast getting of bad cells (precancerous, etc...), and hormones typically only presen

Check writings by Valter Longo. The two principles are autophagy during the fast getting of bad cells (precancerous, etc...), and hormones typically only present in kids during growth periods reappearing during refeeding (eating after fasts longer than a few days).