I switched to a crystal deodorant stick years ago trying to avoid aluminum, because the science was showing that it contributes to Alzheimer's incidence. Now we know that aluminum may also affect estrogen balance. And it turns out that my crystal deodorant may contain aluminum. Better make sure that you check your deodorant for aluminum, and switch if yours is based on "alum" or: potassium aluminunum sulfate".
http://bubbleandbee.blogspot.com/2009/03/aluminum-in-crystal-deodorants.html
http://articles.mercola.com/sites/articles/archive/2010/02/16/aluminum-lurks-in-crystal-deodorants.aspx
thanks to Mercola for the heads up