Two heats
A sauna is dry: 80 to 100 degrees, very low humidity. Sweat evaporates, cooling the skin — which is why such temperatures are tolerable.
A steam room is wet: 40 to 50 degrees, but close to a hundred per cent humidity. Sweat does not evaporate; perceived heat far exceeds the thermometer.
That is why a steam room at 45 degrees can be harder than a sauna at 90.
What is documented
The most consistent studies concern the Finnish sauna: regular use is associated with better cardiovascular health, lower blood pressure and improved sleep.
These are observational associations, in populations where the practice is cultural. They do not establish that the sauna causes the benefits, and nothing shows it "eliminates toxins" — sweat is water and salts, and elimination is the work of liver and kidneys.
Practice
Short sessions — eight to fifteen minutes — rather than one long one. A decisive cooling between each. A rest at least as long as the session. And water: half a litre to a litre is lost per visit.
Never alcohol before or during. Contraindications: unstable cardiovascular disease, marked low blood pressure, pregnancy without medical advice, fever, poorly controlled epilepsy. At any dizziness or nausea, leave immediately — do not wait for the session to end.
Which for whom
Steam suits airways and dry skin better. Sauna suits those who cannot bear the smothering feeling of humidity. People with a low thermal threshold have nothing to gain by forcing themselves.
our piece on rituals sets out how to fit a practice into a regular ritual.
This page is informational and does not replace medical advice.