Hydrogen Water Improves Blood Vessel Function in New Study
Consumption of water containing over 3.5 mg of dissolved hydrogen could improve vascular endothelial function
Research hubs: Cardiovascular System
- Evidence type
- Randomized controlled trial · Human study
- Authors
- Toru Ishibashi, Takaaki Sakai, Bunpei Sato, Koji Hara, Yuichi Hara, Yuji Naritomi, Samon Koyanagi, Hiroshi Hara, Tetsuhiko Nagao
- Journal
- Vascular Health and Risk Management
- Year
- 2014
- PMID
- 25378931
- Study Type
- Human
- Participants
- 36
- Delivery
- Water (Electrolysis)
- Dose
- 500 mL water containing 7 ppm H2 (3.5 mg H2) consumed immediately and with 30-minute interval
- H₂ concentration
- 7 ppm
- Duration
- 1 day or less
- Conflicts of interest
- None declared
- Outcome
- Positive
- Peer Reviewed
- Yes
- Cited by
- 50 (OpenAlex, as of November 2026)
- Country
- Japan
TL;DR
Drinking hydrogen-rich water improved blood vessel function by protecting against harmful molecules in a study, suggesting potential benefits for heart health.
Key Finding
Drinking water containing 3.5 mg of dissolved hydrogen improved blood vessel dilation (a measure of endothelial function) compared to placebo, with the improvement statistically significant.
Summary
This study tested whether drinking water enriched with hydrogen gas could improve how well blood vessels function. Researchers measured the ability of the brachial artery (the main artery in the upper arm) to dilate (widen) in response to increased blood flow in two groups: one that drank hydrogen-enriched water and one that drank regular water. The hydrogen-enriched water group showed improved blood vessel dilation, while the placebo group's dilation actually decreased, suggesting that hydrogen may help protect blood vessels from damage caused by harmful molecules called reactive oxygen species.
Practical Takeaway
This small human study suggests that hydrogen-enriched water may support vascular function, though the study involved only 36 participants and measured only a single acute dose. More research with larger groups, longer durations, and clinical health outcomes would be needed to determine whether regular consumption of hydrogen water provides meaningful health benefits for cardiovascular health.
Abstract (excerpt)
Background: The redox imbalance between nitric oxide and superoxide generated in the endothelium is thought to play a pivotal role in the development of endothelial dysfunction. A third reactive oxygen species (ROS), H2O2, is known to have both beneficial and detrimental effects on the vasculature…