# Effects of Molecular Hydrogen Assessed by an Animal Model and a Randomized Clinical Study on Mild Cognitive Impairment.
> 軽度認知障害に対する水素分子の効果：動物モデルおよびランダム化臨床試験による検討


## Abstract

Oxidative stress is implicated in the pathogenesis of mild cognitive impairment (MCI) and dementia. In a transgenic mouse model overexpressing a dominant-negative form of aldehyde dehydrogenase 2, daily consumption of hydrogen-rich water reduced oxidative stress markers, attenuated memory decline and neurodegeneration, and extended mean lifespan compared with controls. A randomized double-blind placebo-controlled trial enrolled 73 MCI subjects who consumed approximately 300 mL of hydrogen-rich water or placebo water daily for one year. Overall ADAS-cog scores did not differ significantly between groups; however, among apolipoprotein E4 (APOE4) carriers assigned to the hydrogen-rich water group, both total ADAS-cog scores and word recall sub-scores improved significantly. These findings suggest that hydrogen-rich water may help suppress cognitive deterioration, particularly in individuals carrying the APOE4 genotype.

### Mechanism

Hydrogen-rich water consumption reduced oxidative stress markers in a transgenic dementia mouse model, suppressing neurodegeneration and memory decline. In human APOE4 carriers with MCI, hydrogen-rich water was associated with significant improvement in cognitive scores, suggesting a genotype-dependent antioxidant mechanism.

## Bibliographic

- **Authors**: Nishimaki K, Asada T, Ohsawa I, Nakajima E, Ikejima C, Yokota T, et al.
- **Journal**: Curr Alzheimer Res
- **Year**: 2018 (2018-03-14)
- **PMID**: [29110615](https://pubmed.ncbi.nlm.nih.gov/29110615/)
- **DOI**: [10.2174/1567205014666171106145017](https://doi.org/10.2174/1567205014666171106145017)
- **PMC**: [PMC5872374](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5872374/)
- **Study type**: human randomized controlled trial
- **Delivery route**: mixed routes
- **Effect reported**: mixed

## 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 29110615. https://h2-papers.org/en/papers/29110615
> **Source**: PubMed PMID [29110615](https://pubmed.ncbi.nlm.nih.gov/29110615/)