Consumption of water containing a high concentration of molecular hydrogen reduces oxidative stress and disease activity in patients with rheumatoid arthritis: an open-label pilot study
Ishibashi T et al. · Med Gas Res. 2012;2(1):27.
What kind of evidence is this?
Human
Open-label uncontrolled pilot with two treatment periods
Immune and inflammatory conditions
H₂-rich water
Not reported in this record.
Not reported in this record.
Methods at a glance
Adults with rheumatoid arthritis continuing their usual therapy
20 participants
Two 4-week treatment periods separated by a 4-week washout
530 mL/day high-H₂ water for 4 weeks, followed by 4 weeks without it, then another 4-week treatment period
H₂ dissolved in water — H₂ only, not Brown’s gas.
4–5 ppm dissolved H₂ at preparation, described as supersaturated water.
Not applicable — oral water, not gas inhalation.
No O₂ was co-delivered as part of the intervention.
No placebo or concurrent untreated comparator
Outcomes and reported result
Urinary 8-OHdG and rheumatoid-arthritis disease activity score DAS28-CRP
8-OHdG and DAS28 decreased during treatment, but mean DAS28 also continued to decrease during the washout period. The report emphasizes a five-person early-RA subgroup.
Methods and main results checked in the free full text; independent appraisal and complete commercial-support extraction remain incomplete.
A reported association, difference or mechanism is not automatically a clinical benefit. Null findings, outcome type, study design and precision all matter.
Cautions and applicability
Open-label, uncontrolled 20-person pilot; ongoing usual therapy, regression to the mean and the continued improvement during washout make causal attribution uncertain. The five-person subgroup is especially fragile.
Adults with rheumatoid arthritis under continued background care in this pilot.
Not reported in this record.
Not reported in this record.
Not reported in this record.
No single-study GRADE certainty rating is assigned. Certainty is assessed by important outcome across a complete eligible evidence set, not by attaching a final grade to one source.
Sources and record status
PMID: 23031079 · DOI: 10.1186/2045-9912-2-27
Open-access article.
Free full text on PMC; identifiers cross-checked in PubMed.
2026-08-10