Hydrogen Water Shows Promise for Memory Loss in At-Risk Individuals
Effects of Molecular Hydrogen Assessed by an Animal Model and a Randomized Clinical Study on Mild Cognitive Impairment
Research hubs: Brain & Nervous System
- Authors
- Kiyomi Nishimaki, Takashi Asada, Ikuroh Ohsawa, Etsuko Nakajima, Chiaki Ikejima, Takashi Yokota, Naomi Kamimura, Shigeo Ohta
- Journal
- Current Alzheimer Research
- Year
- 2018
- PMID
- 29110615
- Study Type
- Human
- Participants
- 73
- Delivery
- Water, Commercial (Blue Mercury)
- Dose
- ~300 mL of H2-water per day for 1 year
- H₂ concentration
- 0.6 mM
- Duration
- 12 months
- Funding
- Japan Society for the Promotion of Science (23300257); Japan Society for the Promotion of Science (24651055); Japan Society for the Promotion of Science (26282198); Japan Society for the Promotion of Science (23500971); Japan Society for the Promotion of Science (25350907)
- Conflicts of interest
- None declared
- Outcome
- Positive
- Peer Reviewed
- Yes
- Cited by
- 108 (OpenAlex, as of November 2026)
- Country
- Japan
TL;DR
Drinking hydrogen-infused water may help reduce brain damage and memory loss in mice and improve cognitive function in certain people at risk for Alzheimer's disease.
Key Finding
In people with mild cognitive impairment who carry the APOE4 gene variant, drinking H2-water for one year significantly improved cognitive test scores and word recall compared to placebo, though the overall study group showed no significant benefit.
Summary
Researchers tested whether water infused with molecular hydrogen (H2) could help protect the brain from damage caused by oxidative stress (a harmful chemical process). In mice with a genetic condition that causes memory problems, H2-water reduced markers of oxidative stress and slowed memory decline. In a one-year study of 73 people with mild cognitive impairment (early memory problems), H2-water didn't help the overall group, but it did improve memory and cognitive test scores in people who carry a specific gene variant called APOE4.
Practical Takeaway
This early evidence suggests H2-water may help protect memory in people with the APOE4 genetic variant and mild cognitive impairment, but the results are limited to one genetic subgroup in a small study. More research is needed to confirm these findings and determine whether H2-water benefits people without this specific gene variant. Anyone concerned about cognitive decline should consult a healthcare provider rather than relying on H2-water alone.
Abstract (excerpt)
Background: Oxidative stress is one of the causative factors in the pathogenesis of neurodegenerative diseases including mild cognitive impairment (MCI) and dementia. We previously reported that molecular hydrogen (H2) acts as a therapeutic and preventive antioxidant. Objective: We assess…