Individual variability in hydrogen-producing microbes influences the response to hydrogen supplementation on sleep quality: a randomized, double-blind, placebo-controlled, parallel study.
Fumiko Higashikawa, Keishi Kanno · Scientific reports · 2026
Research-use notice
Independent study record
Each H2HUBB study page organizes source-linked research details for educational use. Interpretation should remain proportional to the study design, population, controls, and limitations.
H2HUBB TAKEAWAY
In 44 healthy participants with poor sleep quality, linear mixed-effects model analyses revealed significant interaction effects in the group × H₂-producers in the VAS for sleep quality and mental stress, with greater improvement in participants with a lower abundance of hydrogen-producing bacteria. These findings add human evidence supporting molecular hydrogen's therapeutic potential to influence sleep-related outcomes in healthy adults.
What the Findings Mean
H2HUBB reviewed how hydrogen-supplemented jelly intake affected the outcomes measured in 44 healthy participants with poor sleep quality. Linear mixed-effects model analyses revealed significant interaction effects in the group × H₂-producers in the VAS for sleep quality and mental stress, with greater improvement in participants with a lower abundance of hydrogen-producing bacteria.
What the Researchers Studied
The researchers studied 44 healthy participants with poor sleep quality. The study used a randomized, placebo-controlled human clinical trial. The comparison condition was placebo.
What Effects Did Molecular Hydrogen Have?
Source-reported hydrogen concentration: 100 mM H₂ (≈201.6 mg/L); reported treatment duration: 8 weeks. Linear mixed-effects model analyses revealed significant interaction effects in the group × H₂-producers in the VAS for sleep quality and mental stress, with greater improvement in participants with a lower abundance of hydrogen-producing bacteria. The authors concluded that in conclusion, these exploratory findings raise the hypothesis that baseline gut microbiota composition, particularly microbial hydrogen-producing capacity, may modify individual responses to hydrogen supplementation. Although evidence of the underlying mechanism remains limited, these reports and the authors' current findings suggest that exogenous hydrogen warrants further investigation as a therapeutic strategy for sleep disturbances. In this study, hydrogen supplementation was expected to reduce systemic oxidative stress, as reflected by decreases in markers such as 8-OHdG and isoprostanes.
Why These Findings Matter
These findings add human evidence supporting molecular hydrogen's therapeutic potential to influence sleep-related outcomes in healthy adults and contribute to the growing body of molecular-hydrogen research.
How Strong Is This Evidence?
This is human clinical evidence from a randomized, placebo-controlled human clinical trial. H2HUBB interprets the findings in the context of the study design, sample, comparator, and measured outcomes rather than using one publication as a verdict on hydrogen therapy.
Technical Study Details
H2HUBB classifies this publication as human clinical study with human clinical evidence. The research population or model was 44 healthy participants with poor sleep quality. The reported sample size was 44. The study used a randomized, placebo-controlled human clinical trial. The hydrogen delivery method was hydrogen-supplemented jelly intake. The source-reported hydrogen concentration was 100 mM H₂ (≈201.6 mg/L). The reported treatment duration was 8 weeks.
Limitations and Safety
No separate limitations or safety findings were identified in the current-study source text available to H2HUBB.
Original Study and H2HUBB Research Context
H2HUBB presents this source-grounded research record as one contribution to the broader molecular-hydrogen evidence base.