'Prospective epidemiologic studies performed in large cohorts of men (total: 374,003 subjects) agree in which the risk of suffering Parkinson's disease diminishes progressively as the consumption of coffee and other caffeinated beverages increases. Although tobacco smoking is devastating for longevity or quality of life, it has been related to a reduced risk of having PD. Smokers' risk of having PD may be reduced down to a third when compared to non-smokers. The basis for this effect is not known, but possibilities include an effect of nicotine as a dopamine stimulant.'