I am glad to hear that that has not yet been proven. My mother is constantly yelling at me for using my old Club and Wear-Ever aluminum cookware because she insists that it causes Alzheimers. My Grandmother has always used almost exclusively and is still sharp as a tack at 73 yrs old.
Also just to mention Alzheimers has a lot to do with genetics so excess aluminum is probably not likley.
As for Parkinsons, not long ago I had a directed resading for CE credits in my ASRT book about Parkinsons, and it states that it is most likley caused from genetics and enviromental toxins like pesticides, some of the risk factors are advanced age, family hx, exposure to pesticides and other toxins, working on a farm, drinking well water, and low estrogen levels.