<<Disclaimer: Verify this information before applying it to your situation.>> Good luck with your research. My Ph.D. is in Research & Statistics; my minor is in Psychology. I am also 'irritable' tonight but not because of my bowels but because I have a gluten intolerance and, five days ago, I took a vitamin E capsule that listed 'di-alpha tocopheryl acetate' as the only ingredient. Four days of watery diarrhea, stomach aches and emotional distress later, I find that this capsule also contained wheat germ oil...loaded with gluten. I do not have 'irritable bowel syndrome' nor do I have 'psychological problems'. I have a medical problem that labeling laws make it very difficult for me to live with. One slip...one stinky little inadequately labeled vitamin E tablet containing an ingredient left off the label...and I suffer for four days because of it! I'm irritable, yes. By the way, my bowels work just fine when I stay away from gluten. BJ