Just one packet a day, some days I'll take a second one in the afternoon if I'm feeling off.
My brother also has UC, he's managing on Remicade. Part me believes genetics play a role, other family members have had other digestive system issues (ibs, lactose intolerance and others).
I also believe that random people develop UC. I think stress is a big factor of it coming out or developing far enough to need attention.
As for food, I stay away from green veggies and I don't eat a lot of veggies to begin with. Any normal gas producer (califlower, pops, beans of any variety etc) I try not to have. Otherwise I eat what I want. Lots of sugar or chocolate milk also bother me but I just try not to over do it. I eat lots of bread, meats, cheese, pasta and potatoes.