Saunas and Steam Rooms: Traditional, Infrared and Steam

Heat Practices Beside Water Therapy

Saunas and steam rooms heat the air around you rather than immersing you in water, so they are related heat practices rather than hydrotherapy in the strict sense. They are covered here because spas and bathhouses offer them next to pools and tubs, and many of the same safety points apply, such as fainting and dehydration. This page is an overview. The Biohacking section owns the detailed evidence: Sauna: evidence summary, Infrared sauna: evidence summary and Sauna vs infrared sauna. The pointer page Where sauna and infrared sauna evidence is covered explains the split.

Traditional Sauna

A traditional sauna is a heated room with very hot, dry air. Sauna bathing is a traditional Finnish activity used mainly for relaxation and pleasure. [1] Much of the long-term data comes from Finland, and a review of sauna research noted the studies were most often uncontrolled and used participants who had been bathing since childhood, so results may not carry over to everyone. [2]

How strong is the evidence? In summary:

• Heart outcomes, observational. A large Finnish study of 2,315 middle-aged men found a lower hazard of sudden cardiac death with 4 to 7 sauna sessions per week (hazard ratio 0.37); its authors said further studies are needed to establish the mechanism. [3] This is an association, not proof of cause. A 2019 review described the evidence on sudden cardiac death as uncertain. [1] Label: promising but limited.
• Broader reviews. A systematic review of 40 clinical studies found that most reported beneficial effects, but only 13 were randomized trials and most were small. [4] Label: promising but limited.
• Blood pressure. A 2026 review found heat therapy consistently caused transient blood pressure reductions, while long-term benefit is unproven. [5] Label: insufficient evidence for lasting effects.

Infrared Sauna

Infrared saunas use heaters that warm the body more directly than the air. A meta-analysis of 7 studies found infrared sauna associated with short-term improvement in cardiac function in people with heart conditions, with evidence strength from moderate to insufficient. [6] For healthy people, claims that infrared saunas are superior to traditional saunas are marketing claims: the reviews read here did not compare them directly. Proper evidence not found in those reviews for a general-wellness advantage.

Steam Rooms

A steam room is a very humid heated room. The humid-room tradition has many names and histories; see Hammam, Turkish baths and Roman baths. For specific health benefits of steam rooms as such, proper evidence not found: PubMed searches for steam room, steam bath and hammam returned a trial of a combined hammam and massage program (see the steam rooms and steam baths guide) but no trials of a steam room alone.