What is hydrogen water?
It is drinking water with extra hydrogen gas dissolved in it. You may also see the name “hydrogen-rich water”.
Water, with added gas
The water stays water. The added ingredient is hydrogen gas dissolved in it.
Tablets or devices
Purpose-made magnesium-metal hydrogen tablets release hydrogen gas in water. Some bottles and machines use electricity to make hydrogen.
The amount can change
The amount of hydrogen may fall after preparation. How the water is made and stored matters.
Remember: A result from one water preparation does not show that every tablet or device has the same effect.
Looking at another administration form? Molecular hydrogen inhalation means breathing a hydrogen-containing gas. Water-study results do not automatically apply to that route.
How do magnesium tablets make hydrogen water?
Some purpose-made hydrogen tablets contain magnesium metal. In water, the magnesium reacts (in some formulations with food or organic acids) and releases hydrogen gas (H₂); some of this gas dissolves in the water.
An ordinary magnesium supplement is not the same as a hydrogen-generating tablet. Milligrams (mg) of magnesium per tablet describe the amount of magnesium; milligrams per litre (mg/L) of dissolved H₂ describe the hydrogen concentration in the water.
Bubbles alone do not identify the gas or measure hydrogen concentration.
See a study that used these tablets — Kura et al., Antioxidants, 2022, 11(10), 1935.
More about hydrogen water — details and sources
How do water-generating devices work?
Some bottles and machines use electricity to produce hydrogen from water. This process is called electrolysis. Hydrogen is then dissolved in the drinking water.
Designs differ. A device may separate the gases or use a separate hydrogen supply.
To check a claim, testing needs to measure hydrogen dissolved in the water at a stated time. Seeing bubbles is not enough to measure that amount.
Is this the same as alkaline water?
No. “Alkaline” describes the water’s acidity level, measured as pH. “Hydrogen water” describes dissolved hydrogen gas.
Those are different properties. A pH reading alone does not tell you how much hydrogen is dissolved in the water.
What information helps compare preparations?
- How was the water made?
- How much dissolved hydrogen was measured?
- Was it measured before drinking, or only when first prepared?
- What other ingredients were present?
- What did the study compare it with?
A number on a label needs a clear unit and measurement method.
What can the studies tell us?
Human studies test particular products, groups of people and outcomes. Results can differ across studies.
Changes in laboratory measurements do not always mean a useful change in health. Research about inhaled hydrogen cannot simply be reused as evidence for hydrogen water.
Sources and reading limits
- ClinicalTrials.gov protocol NCT03320018 — hydrogen-producing tablets, preparation section
- Islam et al., Scientific Reports — water-generator method (not human health evidence)
Source-linked explanatory information. Supplier specifications are not clinical evidence or independent device measurements.
Understand the equipment
Tablets, electrolysis and infusion
Generation, dissolved concentration, water quality, added ingredients and measurement timing are separate questions. A water-flow figure is not a gas dose.
Read the model, not the marketing
The directory identifies supplier claims, unknowns, source dates and disagreements. Inclusion is not independent testing, approval or a recommendation.
Explore published studies
Browse all 230 hydrogen-water records
Human and preclinical records remain distinct; biomarkers are not automatically clinical benefit.