Definition
Because “hydrogen therapy” is loose, it is best treated as a search phrase rather than a specification. A bath, a cannula session and a glass of hydrogen-rich water share only the molecule; their formats, doses and logistics differ entirely.
Anyone comparing options should resolve the phrase into a modality plus a production method before comparing numbers.
Modality relevance
The phrase spans all three consumer formats. On this site, inhalation and bathing are the two supported device modalities.
Purity relevance
Whichever modality is chosen, the purity conversation is about the electrolysis cell and gas path — hardware, not health.
Science relevance
Published work is exploratory and mechanism-focused. Nothing here should be read as evidence that a device treats a condition.