Whey is made from milk, so you probably would want to stay away from that if you don't do dairy. Soy powders aren't necessarily bad for you, but like anything, it's better to eat the food in it's unprocessed natural state (soybeans) rather than the isolated protein. There are other types of protein powders available besides whey and soy that you might want to consider - I know Kathryn knows a lot about these, so I'm sure she'll chime in here. I've used soy protein powder before (Spirutein), and it's pretty good. Some people feel bloated when they use soy powder, but that's never happened to me.