I was talking with my school's principal today related to a totally separate issue when you mentioned kids with sensory issues and noted an example of a kid who would throw up every time he entered the cafeteria. It immediately reminded me of this post. I would definitely seek out an eval for possible sensory issues and find out a solution that will work for your kid to be able to eat and be comfortable. Good luck!

Interesting, OP. Sorry he's dealing with this. As someone with misophonia, this sounds vaguely familiar to me. I never feel nauseous with others' eating, but I do feel angry and repulsed. CBT may help.

Any physical cause should be ruled out first, but kids often have psychosomatic illnesses.

Maybe he has intestinal worms or too much bad bacteria in his stomach. People used to know that humans need to be de-wormed just like animals but somehow that has been lost. Everything isn't a mental health issue, most of you sound like loons.

Definitely work with the guidance counselor and teacher and seek an outside eval. Have you called your ped for advice on next steps? It could be any number of different things and is a good idea to look into it on many levels while also making it possible for him to continue to thrive at school -- in whatever way he can manage to eat without throwing up. Seems like it could be a sensory issue of sorts.