Re: Can eating a raw onion cause a cold?
I know this is an older post, but I just wanted to share what happened to me when I was a kid... I used to love eating toothpaste (I know it's weird, but I was a weird kid!). Not a lot, just as much as I'd brush my teeth with... I'd squeeze out some and eat it. One night I did this, and all of a sudden my throat started burning and it hurt so bad! I thought all the things my mom had warned me about eating toothpaste had come true! My mom took me to the doctor the next day because it hurt so bad to swallow, I couldn't eat. Turns out I had strep. The toothpaste had just gotten into the strep sores and that's why it burned so badly.
I would imagine the onion acted in the same fashion. You were probably already on your way to having a cold and your natural reaction to the spiciness of the onion (and the previous spicy food you mentioned) just exaggerated your symptoms.
Onions and certain other spicy foods (cayenne pepper, cinnamon, etc) are actually used to naturally treat colds and respiratory illnesses.