Hunger

You are expected to eat something, occasionally, or take a debuff that incurs -10 to all stats (str/dex/int) until you are Well Fed.

It will take approximately 8 in-game hours for a player to start feeling hungry again, and 15 in-game hours to starve.

Hunger Status
You will be alerted in chat when you reach the following statuses and an icon will appear at the top when you are hungry or starving:
 * Well Fed
 * Peckish
 * Hungry
 * Very Hungry
 * Starving (the debuff occurs when you are Starving)

Eating until Well Fed is the optimal way to extend how long you'll stay full for. It is not ideal to eat until you are just Peckish.