It's an interesting question, some say it's empathy. There have been studies done that show just watching someone, say eat an ice cream, stimulates parts of the brain that are used when actually eating it...others have postulated that yes, it is an instinct survival trait, in that if someone vomited, it was due to poison and so the rest would do the same if they had eaten the same thing.
I take omeprazole which suppresses the production of stomach acid. That is soo lovely because I currently have labyrinthitis which causes frequent upchucks. Returning a stomach full of coffee is just like spitting out coffee. No smell no other taste. Omeprazole is a drug I would take from choice. :)
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