Smelly breath yes, smelly skin - not heard of that one before. Use Listerine strips for the breath or keep a toothbrush to hand. If you're worried about the skin thing just keep a deodorant on you at all times
Breath does get a bit nasty but there is mouthwash and sprays you can use but i would ask the more experianced on here what ones to get (there may be a prev post already)
Drinking more water helps.....
As fattothin says you may not get any side effects at all. I was really worried about getting headaches and feeling lethargic etc, etc, but I have been fine and if anything feel better than before I started. I have lots of energy and just feel so much better. You will be fine and do not worry about any side effects you have heard about.
I am neurotic about having bad breath but find if you drink plenty of water things are fine - no-one has commented on mine and I work with teenagers who don't hold back!!!!!! As for the skin thing, I must admit I am aware of it, BO and not having it is another thing I'm neurotic about (the only things I promise I'm not a basket case or anything!!!!!!) and I have noticed more of a smell since starting, not bad just slightly stronger than normal, although no-one else has said anything!