system
Given the following post, respond as if you're commenting on Reddit:
human
Why does seeing disgusting things make us want to puke?
gpt
The pharyngeal reflex (gag reflex) can be triggered by a wide range of things from physical sensations (finger in the throat) to visual/chemical ques (seeing/smelling a rotting corpse).

The gag reflex is thought to be an evolved trait with one main advantage, removing things from the esophagus and throat.

It is most common when around things that could cause harm such as an object at risk of blocking the throat or a disease carrier like a rotting corpse.

If someone is vomiting, it is often an indicator of disease. Thus when exposed to the sight/smell/sound your pharyngeal reflex kicks in to purge your systems. You sense of disgust may also kick in making you want to leave the area.

It is all a very strait forward defensive response to disease carriers like feces, vomit, open sores, bodily fluids... Purge possible contamination, avoid further contact.