# Trend of research on the medical use of molecular hydrogen: a bibliometric analysis.
> 分子状水素の医療応用に関する研究動向：書誌計量学的分析


## Abstract

A bibliometric study examined 1,126 PubMed-indexed publications on the medical use of molecular hydrogen published through July 2021. Annual publication counts showed a consistent upward trajectory from 2007 to 2020. Keyword co-occurrence analysis identified oxidative stress, inflammation, hydrogen-rich water, and hydrogen gas as the most frequently appearing terms. More recently emerging keywords included gut microbiota, pyroptosis, and COVID-19, suggesting these as potential future research hotspots. The analysis provides a structured overview of how the field has evolved and where investigative interest is likely to concentrate in coming years.

### Mechanism

Oxidative stress and inflammation represent the dominant mechanistic themes in the literature; gut microbiota modulation and pyroptosis are identified as emerging mechanistic areas of interest.

## Bibliographic

- **Authors**: Li H, Ma HY, Hua WL, Zhang YJ, Zhang LL, Xing PF, et al.
- **Journal**: Med Gas Res
- **Year**: 2023
- **PMID**: [37077121](https://pubmed.ncbi.nlm.nih.gov/37077121/)
- **DOI**: [10.4103/2045-9912.344980](https://doi.org/10.4103/2045-9912.344980)
- **PMC**: [PMC10226689](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10226689/)
- **Study type**: review
- **Delivery route**: mixed routes
- **Effect reported**: not assessed

## Delivery context

This study combines multiple delivery routes. As a general principle, the most efficient route for routine hydrogen intake is inhalation. Inhalation carries explosion risk (empirical LFL of 10%; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

## Safety notes

This study combines multiple delivery routes. As a general principle, the most efficient route for routine hydrogen intake is inhalation. Inhalation carries explosion risk (empirical LFL of 10%; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

See also:
- [Inhalation concentration and LFL / UFL](https://h2-papers.org/en/safety-notes/inhalation-concentration)
- [Consumer Affairs Agency accident cases](https://h2-papers.org/en/safety-notes/accident-cases)
- [Inhalation safety threshold lineage](https://h2-papers.org/en/safety-notes/lineage)

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> **Cite as**: H2 Papers — PMID 37077121. https://h2-papers.org/en/papers/37077121
> **Source**: PubMed PMID [37077121](https://pubmed.ncbi.nlm.nih.gov/37077121/)