Sauna bathing is inversely associated with dementia and Alzheimer's disease in middle-aged Finnish men

Objective: To evaluate whether regular sauna bathing is associated with reduced risk of dementia and Alzheimer's disease in middle-aged men. In this prospective cohort analysis, baseline sauna habits were recorded and participants were followed for incident neurodegenerative outcomes over time. Higher frequency of sauna use was associated with lower observed incidence of dementia and Alzheimer's disease, with the strongest inverse associations among men who bathed most often. The authors suggested several possible pathways, including improved vascular function, blood pressure reduction, stress relief, and broader cardiometabolic benefits that might indirectly protect the brain. However, because exposure was self-reported and sauna use correlates with multiple lifestyle factors, causal inference is limited. The study does not prove a neuroprotective effect, but it raises a hypothesis-generating association that has since attracted attention in preventive neurology. Replication in other populations and with stronger control for confounding would be required before clinical recommendations could be made.