Interesting. Is there any research showing lower rates of Alzheimer's in smokers? Of course, since Alzheimer's is usually a very late onset disease, it might be hard to document the effects of smoking, since smokers are much less likely to survive to the average Alzheimer's onset age.
In an article in The Times of London (9/7/93), Dr. James Le Fanu provided an examination of the research on smoking and its apparent protective effect for certain diseases. Dr. Le Fanu stated unequivocally: "Smokers have a 50 per cent reduced risk of developing Alzheimer's--and the more smoked the greater the protection." He also noted that emerging research points to a similar effect of smoking on Parkinson's disease.