Hydrogen Water Shows Rapid But Short-Lived Absorption in Breath Tests
Breath hydrogen produced by ingestion of commercial hydrogen water and milk
Research hubs: Respiratory System
- Evidence type
- Uncontrolled trial (single-arm or pilot) · Human study
- Authors
- Akito Shimouchi, Kazutoshi Nose, Makoto Yamaguchi, Hiroshi Ishiguro, Takaharu Kondo
- Journal
- Biomarker Insights
- Year
- 2009
- PMID
- 19652760
- Study Type
- Human
- Participants
- 5
- Delivery
- Gas
- Dose
- hydrogen water ingestion in varying doses
- H₂ concentration
- 0.21 to 0.58 mM
- Duration
- 1 day or less
- Funding
- Ministry of Education, Science, Sports and Culture of Japan (Grant-in-Aid 16209020); Japanese Promotion of Science
- Conflicts of interest
- None declared
- Outcome
- Neutral
- Peer Reviewed
- Yes
- Cited by
- 30 (OpenAlex, as of November 2026)
- Country
- Japan
TL;DR
Drinking hydrogen water quickly raises the level of hydrogen in a person's breath, but not as long-lasting as when drinking milk, especially in those who are milk intolerant.
Key Finding
Hydrogen water rapidly increased breath hydrogen levels to peak concentrations within 10-15 minutes in a dose-dependent manner, but this elevation was not sustained, whereas milk produced a delayed but prolonged hydrogen response lasting up to 540 minutes.
Summary
This study measured how much hydrogen gas appears in people's breath after they drink hydrogen water or milk. Five adults drank hydrogen water or regular water, and researchers measured hydrogen levels in their breath over time. Hydrogen water caused breath hydrogen to spike quickly (peaking within 10-15 minutes) and then drop back to normal, while regular water had no effect. Milk produced a slower but much longer-lasting increase in breath hydrogen, especially in people who have trouble digesting milk.
Practical Takeaway
This small study (5 people) shows that hydrogen water does deliver hydrogen gas into the body, but the effect is brief. The practical significance of this rapid, short-lived hydrogen spike is unclear—the study only measured whether hydrogen appeared in breath, not whether it produced any health benefits. More research is needed to determine if the brief hydrogen exposure from drinking hydrogen water has any biological effects.
Abstract (excerpt)
Objective: To compare how and to what extent ingestion of hydrogen water and milk increase breath hydrogen in adults. Methods: Five subjects without specific diseases, ingested distilled or hydrogen water and milk as a reference material that could increase breath hydrogen. Their end-alveolar…