Researchers have discovered that people who drink coffee regularly have significantly lower rates of Parkinson's disease than non-coffee drinkers. The relationship is dose-dependent: those who drink more coffee have even lower rates of the disease. This finding has been replicated in studies across different populations. Coffee must therefore have a protective effect against Parkinson's disease, possibly due to its caffeine content or antioxidants. Public health authorities should promote coffee consumption as a preventive measure against this debilitating neurological condition. Critics argue that we do not fully understand the mechanism by which coffee might protect against Parkinson's, but we do not need to understand the mechanism to recognise that coffee prevents the disease. The epidemiological evidence is clear and consistent.