I have so much food allergies since I was a baby.
Sesami oil, almost every single nuts.....
Yesterday I went to eat curry near the school. It had nuts(maybe peanuts?) in it and I didn't realize it until I almost finish eating it. As I know that I have an allergy, I always bring my medicine with me and I had it right away. During my way home I threw up two times (sorry that its disgusting for people reading this) and I wasn't able to talk normally cause my food passage got swollen. It was the serious fit I've ever experienced in my life so I thought I would die. Luckily it was no school today so I was able to take a great amount of rest.
If you have a friend that have a food allergy, it may be a quite serious one, so don't treat the matter lightly please! :)