Well tanning (which I used to do), come to find out causes cancer, melanoma to be specific (which my fiance passed away from in 1987), so even though I was a heavy tanner (for my professional Brazilian foclorico and samba dancing), it was very, very bad for my skin.
I have not studied, nor heard anything about bleaching. If you're speaking of all the gossip junk about Michael Jackson, that's just cruel, for anyone to be treated the way he was.
The bleaching thing or whatever they use, as I understand it, is for people who have the same condition Michael Jackson had - I had an old roommate with that who was from Peru, she would just put on tons of make up to make herself darker.
Any negative talk about anyone is just not nice (even though we all do it at times), but if we're more mindful about what we say, it won't happen as often and the world will be a better place. :-D
Crickity 'ole 50 year old