Some people have no problem quitting cigarettes It's probably genetic Also it seems to correlate with risk of Parkinson's http://www.medscape.com/viewarticle

Some people have no problem quitting cigarettes It's probably genetic Also it seems to correlate with risk of Parkinson's http://www.medscape.com/viewarticle/832391 http://www.medscape.com/viewarticle/832391 ( huh that seems to be paywalled? Google "Ease of Quitting Smoking May Be Early Sign of Parkinson's")