Is it sulfur or tyramine?

I have migraines and upset stomach from eating raw or even just partially cooked onion. I usually read that tyramine is the culprit. I also will get an immediate headache around diesel fumes, which contains sulfur. The same kind of headache I get with onions. I won't get a migraine from eating aged cheeses, but an upset stomach and diarrhea will surely occur if I eat enough of it. Pain killers don't help, but Pepcid type products will help some with the headache. I've given up eating food with a lot of aged cheese and the stomach issues went away with it. Any amount of raw onion will do it, my son also has this issue and so did my father. Any one else out there got a similar issue?