Minecraft wiki entry for Healing, associated text: When the difficulty is set to Peaceful, the player regenerates at a standard rate of 1 per second, additionally with 1 every 4 seconds as the player's hunger bar is filled. Chorus fruit, golden apples, honey bottles, and suspicious stew can be eaten even when the hunger bar is full, increasing the player's regeneration even further. On the other hand, this also causes the player to lose saturation even when changing from other difficulty levels to Peaceful mode.