Is Sauna worth prioritizing?

A well-known Finnish cohort study (KIHD) found frequent sauna bathing (4-7 times per week) was associated with substantially lower fatal cardiovascular and all-cause mortality compared with once weekly, a finding extended by related analyses from the same cohort linking sauna use, cardiorespiratory fitness, and reduced risk of sudden cardiac death. Weighing that against the numbers, Sauna is a strong candidate to prioritize — it combines strong evidence (71/100) with a high estimated impact on longevity (63/100).