Many fail to realize that there is a distinction to be made (but it is purposely not made by the leftist media whores) which is crucial to the public debates, namely that there are stem cells in the embryo that are the body parts of the embryonic individual human being and to harvest those is to kill the INDIVIDUAL; there are stem cell sources that do not require the killing of another INDIVIDUAL LIFE--those cells are called 'adult stem cells'.
As far as I'm aware, there is no definitive word on a correlation between smoking and Parkinson's or Alzheimers. There is a genetic predisposition to both diseases however.
I had a very interesting business proposal presented on this very topic.
Is this an intentional quote from the Book of Leviticus?
I do not know about "definitive word" but negative correlation is there.