Along comes a stressful period that lasts months. Your body cuts down on its acid secretion—there are now frequent times when digestion is being inhibited. During this period, your stomach essentially decides to save itself some energy by cutting corners. It cuts back a bit on the constant thickening of the stomach walls, undersecretes mucus and bicarbonate, and pockets the difference. Why not? There isn’t much acid around during this stressful period anyway.