“Our body is undergoing the rest-and-digest phase when sleeping, a part of the autonomic nervous system that allows the fight-or-flight response to shut off,” Medina tells mbg. It’s a vital time when your body is digesting and absorbing nutrients, metabolizing food, and building up your immune system.
But digesting a day’s worth of meals and snacks is only half the battle. At the same time your digestive system is breaking down food particles, it’s also regenerating new cells to replace old ones. This is just as important of a process, Medina notes, as it helps keep the lining of your intestine strong and tight, therefore preventing larger proteins or bacterial substances from entering the bloodstream.