Eli5 How does food and liquids remain inside the stomach and not “leak out of your mouth” whilst being in space?

Question

Eli5 How does food and liquids remain inside the stomach and not “leak out of your mouth” whilst being in space?

In: 82

Answer 1

There is a muscle at the top of your stomach. It is a ring that holds closed unless you are swallowing or puking. This is why you can be upside down and won’t have what’s in your stomach pour out. Same thing as why you don’t pee yourself each time you stand as there is one right at the exit of your bladder. These types of muscles are all through the body and control the flow of liquids.