Fake Science: Smoking and Parkinson's Disease

While browsing the internet for articles about Parkinson's disease I came across a claim that "smokers are less likely to get the disease than non-smokers." This appeared in several sites, including Wikipedia. Well, there is a simple explanation for the correlation. Smokers have a lower life expectancy than non-smokers (by about 10 years). And the chance of getting Parkinson's rises steeply with age! See the diagram below. So do not start smoking hoping to be protected against Parkinson's.