# Effects of hydrogen rich water and pure water on periodontal inflammatory factor level, oxidative stress level and oral flora: a systematic review and meta-analysis.
> 水素水と純水が歯周炎の炎症指標・酸化ストレス・口腔内細菌叢に与える影響：系統的レビューとメタ解析


## Abstract

A meta-analysis was conducted to evaluate the effects of hydrogen-rich water (HRW) compared with pure water on periodontal and peri-implant conditions. Seventeen randomized controlled trials involving 304 participants, published before March 2022, were identified across seven major databases. Pooled analyses showed that HRW significantly reduced IL-1β (SMD = −0.73), TNF-α (SMD = −2.51), IL-6 (SMD = −1.31), 8-hydroxyguanosine (SMD = −1.61), and reactive oxygen metabolites (SMD = −0.49), while glutathione peroxidase activity increased (SMD = 2.5). Oral pathogenic bacterial activity was also markedly suppressed (SMD = −0.91). Overall bias risk across included studies was rated as medium to low. These findings indicate that HRW exerts measurable anti-inflammatory, antioxidant, and antimicrobial effects in patients with periodontal disease.

### Mechanism

HRW selectively scavenges reactive oxygen species, thereby reducing pro-inflammatory cytokines (IL-1β, TNF-α, IL-6) and oxidative stress markers while upregulating glutathione peroxidase activity and suppressing oral pathogenic bacterial proliferation.

## Bibliographic

- **Authors**: Bai Y, Wang CY, Jiang H, Wang L, Li N, Zhang W, et al.
- **Journal**: Ann Transl Med
- **Year**: 2022
- **PMID**: [36388830](https://pubmed.ncbi.nlm.nih.gov/36388830/)
- **DOI**: [10.21037/atm-22-4422](https://doi.org/10.21037/atm-22-4422)
- **PMC**: [PMC9652511](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9652511/)
- **Study type**: meta-analysis
- **Delivery route**: hydrogen-rich water
- **Effect reported**: positive

## Delivery context

Hydrogen-rich water is a low-risk delivery route, but the achievable systemic hydrogen dose is bounded. For clinical applications, inhalation is the most efficient route; inhalation, however, carries explosion risk, and concentration matters (empirical LFL of 10% applies to inhalation environments; high-concentration devices are documented in the Consumer Affairs Agency accident database and are not recommended).

## Safety notes

Hydrogen-rich water is a low-risk delivery route, but the achievable systemic hydrogen dose is bounded. For clinical applications, inhalation is the most efficient route; inhalation, however, carries explosion risk, and concentration matters (empirical LFL of 10% applies to inhalation environments; 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 36388830. https://h2-papers.org/en/papers/36388830
> **Source**: PubMed PMID [36388830](https://pubmed.ncbi.nlm.nih.gov/36388830/)