I have no idea what originally triggered my UC - from what I remember it was that I got food poisoning and a few weeks later my colon started bleeding.
But I can say, without a doubt, that not one person on this forum is exactly the same as anybody else with UC. What works for one may not work for another. I treat this forum as a way to get suggestions and give suggestions. What may work for me may not work for another and vice versa. But hey, if it does work for me all I can do is say 'here's what works for me, try it if you like but it may not help you' and let others take it from there.
My brother also has UC, or had it for about 4 years than had to have j-pouch surgery because no meds ever helped him. Me, on the other hand, have had UC for 19 years with no surgery and never as bad off as he was. Meds have worked for me. This is an excellent example of what works for one does not work for another.
Stress is for sure the trigger for my UC. But that can be a hard one to control as sometimes things happen in your life that you just cannot control. But I try darn hard to make deal with stress the best I can.
In my opinion, if something is working for me and helps me lead a normal life, I could care less what it is - meds, yoga - who cares as long as I'm not sick.
Oh and on a final note, I am absolutely, postively, SURE that food has nothing to do with my UC (that was the original question, wasn't it)? :) Food does upset my IBS, but that is just temporary and right back to normal the next day.