system
Given the following post, respond as if you're commenting on Reddit:
human
How do the body regenerate the stomach acid after we've vomited?

How long does it usually take and (providing I've essentially emptied my stomach), how long should I wait until I eat again?
gpt
Parietal cells in the gastric endothelium (cells lining the stomach) produce acid (HCl) in response to various signals, including changes in stomach pH and hormones like histamine and gastrin.  The amount of time varies a lot, but eating after vomiting won't probably hurt you, though you might vomit again.  The stomach will naturally increase production of acid and digestive enzymes in response to any food you put in it.