I don't know if this is unusual to me, but whenever I try to take most vitamin supplements, I get incredibly nauseated and feel like I'm going to throw up. Sometimes I actually do. I've tried them with or without food, it doesn't seem to really make a huge difference. I've tried the kind without iron (since that can be difficult on your stomach), no difference. I've tried vitamins from the health food store and vitamins from the drugstore, different brands and formulations... everything makes me sick to my stomach.

That's probably reason #1 why I don't take vitamins. :)

If I feel like I'm really in need of vitamins, I'll make myself a smoothie with Spirutein protein powder - it's got a lot of the same vitamins and minerals, plus soy protein, plus it doesn't make me ill.