system
Given the following post, respond as if you're commenting on Reddit:
human
How does digestion work when you're upside-down? If hung upside-down, would you eventually starve, even if you had food?
gpt
No, the smooth muscles in your esophagus will push the food down into your stomach independent of gravity. This is why you can take a gulp of water upside down.

As for the stomach and intestines, they also have layers of smooth muscle called tunica muscularis that maintain peristalsis in order to keep the food going in the right direction.