What happens when my hunger bar becomes empty?

Assuming you are playing Minecraft my frn. The consequences of having an empty hunger bar depend on the difficulty you are playing Minecraft in. When playing on Easy difficulty, your health will slowly drain until you have 10 units of health left (5 heart icons), at which point the damage will stop. On Normal difficulty, your health will drain until you are left with 1 unit of health (half of a heart). On Hard and Hardcore difficulty, you are capable of dying from starvation; your health will continue to drain until you die. Your Sim dies.

Your Sim dies.