LOL, it was Key from SHINee that told her to go on a diet.
They are good friends, well, from I read, they say that they are good friends.
I personally think Nicole is good the way she is.
There really is no need for her to go on a diet. @_@
I have to say, Nicole is. However, without the other people, I doubt the performance would be as good. Therefore, I think everyone helps make this performance great!