This will probably be quite repetitive at this point but here goes (pretty much in order of severity):
Foods... Dairy (anything and everything, even teeny tiny amounts) Anything greasy or high fat (red meat, fats, egg yolks etc.) IF (especially raw veggies (can't touch em), and less so in whole grains) Alcohol (only takes a few sips) Onions, peppers, corn, broccoli, tomatoes - even cooked - as well as any citrus fruits Artificial sweeteners, HFCS Cold water or other drinks (anything I drink is pretty much always lukewarm, heh) - or really chugging any liquids at all Anything carbonated Caffeine (don't drink coffee but decaf regular tea is usually ok for me)
Lifestyle... Not eating often enough Eating too much at one sitting Lack of sleep Stress Not getting enough exercise First few days of my period (always get D, no matter what)