Why does an ozone sauna deliver ozone through the skin rather than having you breathe it?

The design point

The sauna used for ozone sessions is the kind where your head protrudes from the top of the cabinet, so you are not breathing the ozone and steam mixture. The neck opening is covered for the same reason. Everything below the neck is enclosed; the airway is not.

What happens at the skin

The everyday explanation — that ozone simply enters through open pores — is a simplification. The account drawn from Dr Velio Bocci’s work is more specific:

• Ozone dissolves readily in water, including the thin film covering the skin.
• Being a potent oxidant, it reacts immediately with ions and biomolecules in that fluid, preferentially polyunsaturated fatty acids.
• That reaction consumes the ozone and generates hydrogen peroxide and lipid oxidation products (LOPs) — the chemicals formed when an oxidant attacks fats, particularly those in cell membranes.

Ozone does not travel around the body as ozone. It reacts where it lands.

How much actually gets in

Transdermal ozone uptake has not been quantified, so what we publish is what the equipment delivers rather than a dose: about 47 ppm in the sauna’s air from a 500 mg/h generator on a 2 l/min oxygen feed, adjustable across ten levels.

Why steam is part of it

Steam raises skin temperature and hydration, which the research on our steam studies page links to increased permeability of the stratum corneum. A review cited there describes steam at roughly 35–40 °C creating a thermally reversible transition in skin lipids.

A note on dose

How an effect changes as the dose changes is called a dose-response relationship, and in ozone therapy it is often framed as hormesis, where a small dose has the opposite effect to a large one. It is part of why output is adjustable, and a reason not to assume that more ozone is better.