Minecraft wiki entry for Hunger_management, associated text: When exhaustion reaches 4, it resets to 0, and saturation decreases by 1. When saturation reaches 0, the hunger bar will start to visibly ripple, and hunger starts to drain away in place of saturation. (As a result, a way to visualize saturation is to think of it as an "extra hunger bar" above your hunger bar, that gets deducted before hunger at the same speed.) When your hunger drops below 18 ( × 9), you stop healing automatically. When it is at 6 () or below, you will be unable to sprint. Also, when your hunger drops to 0 (), you start to take starvation damage. On Easy mode, starvation damage will not lower you below 10, while on Normal mode, it can reduce you to 1. On Hard mode, starvation can kill you.