Association of self-selected hydrogen-rich water consumption with 6-month changes in chair-stand performance and gait speed among community-dwelling older adults attending community salons
Harada Y, Miyakawa M. · Journal of Frailty, Sarcopenia and Falls. 2026;11(2):137–143.
What kind of evidence is this?
Human
Prospective non-randomized observational cohort with adjusted and sensitivity analyses
Exercise and recovery
H₂-rich water
Not reported in this record.
Not reported in this record.
Methods at a glance
Community-dwelling older adults attending resident-led community salons in Hiroshima, Japan, without long-term-care/support certification.
128 participants classified by self-selected use at baseline: routine H₂-water consumers n=64 and non-consumers n=64.
Baseline and six-month physical-function assessments.
No assigned intervention; consumers routinely drank salon-distributed H₂-rich water, reportedly up to 600 mL/day.
H₂ dissolved in drinking water — H₂ only, not Brown's gas and not inhalation.
Product label reported approximately 1.05 mg/L dissolved H₂. Neither actual daily volume nor H₂ concentration at consumption was directly measured.
Not applicable — drinking water; preparation flow was not reported.
No O₂ was co-delivered as part of the observed H₂-water use.
Salon attendees who did not routinely consume the distributed H₂-rich water; use was self-selected rather than randomized.
Outcomes and reported result
Thirty-second chair stand, usual gait speed, Timed Up and Go, one-leg stance and grip strength.
Adjusted chair-stand, gait-speed, one-leg-stance and grip-strength values favored consumers at six months. Timed Up and Go did not clearly differ (adjusted difference −0.39 s, 95% CI −1.23 to 0.45).
The complete free PMC article, statistical methods, tables and discussion were checked for exposure definition, direct-measurement gaps, adjusted positive and null outcomes, limitations and disclosures.
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
Observational self-selection cannot establish causality; health behavior, salon attendance, exercise, comorbidity, nutrition and medicines may confound results. Intake and H₂ concentration were not verified and biomarkers were not collected. Authors reported no conflict; no explicit funding statement was identified, so absence of funding is not inferred.
Active community-salon attendees in Japan; associations should not be presented as proof that H₂ water improves mobility or prevents falls.
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: 42232098 · DOI: 10.22540/JFSF-11-137
Free full article in PubMed Central.
Complete PMC article and PubMed metadata; full-text extraction checked 9 August 2026.
2026-08-10