# Sauna and Cardiovascular Prevention

Sauna changes cardiovascular physiology and may improve selected clinical function, but the evidence does not yet establish that habitual sauna itself prevents hard cardiovascular events across adults.

Primary-subclaim aggregation returns SC2 Γ: prospective mortality associations and meaningful controlled physiology/function supply a coherent biological rationale, while same-scope hard-event causal identification remains unverified. This is unconfirmed prevention, not evidence that sauna is physiologically inert or that every heat, cold or neuromodulation intervention is ineffective.

These are experimentally observed physiological or therapeutic-context boundaries, not a mapped hard-event benefit that generalizes to all adults. Finnish observational mortality gradients, supervised Waon, water immersion and localized heating remain distinct. The registered prevention endpoint is not replaced after seeing the outcomes.