NOT ALL HYDROGEN TECHNOLOGIES DO THE SAME THING
When I originally wrote this article in 2017, the consumer molecular hydrogen industry was still young. Portable hydrogen bottles, hydrogen tablets, dedicated infusion machines, water ionizers, hydrogen inhalation devices, and other delivery technologies were only beginning to become familiar outside parts of Asia.
The industry looks very different today.
We now have pressurized hydrogen water bottles capable of producing several milligrams of H₂ in a small serving, larger PEM/SPE pitchers, dedicated infusion systems, pressurized dissolution systems, hydrogen tablets producing high concentrations, ready-to-drink hydrogen water, and inhalation machines ranging from compact portable systems to high-output devices.
But one principle from the original article has become even more important:
The name of the technology does not tell you how much molecular hydrogen the product actually delivers.
At H2HUBB, we care about the complete delivery system: how H₂ is produced, how it is transferred, how much reaches the user, whether that performance is repeatable, and whether the product meets appropriate safety requirements.
Originally published December 19, 2017. Updated August 26, 2026.
H2HUBB Takeaway
- There are multiple legitimate ways to deliver molecular hydrogen. Drinking hydrogen-rich water, inhaling H₂, using hydrogen tablets, hydrogen baths, and specialized research routes all deliver the same molecule in different ways.
- Hydrogen-water technologies are not interchangeable. PEM/SPE bottles, infusion systems, pressurized systems, water ionizers, tablets, and packaged hydrogen water use different engineering approaches.
- Producing H₂ gas is only half the problem. For hydrogen water, the hydrogen has to actually dissolve and remain in the water long enough to be consumed.
- Concentration is not the same as total dose. For hydrogen water, mg/L must be considered together with serving volume to determine the approximate milligrams of H₂ delivered.
- H2HUBB compares measured performance, not technology labels. Products using the same general technology can perform very differently in real-world testing.
First: Molecular Hydrogen Methods and H₂ Technologies Are Not the Same Thing
Before we compare products, I think it helps to separate two ideas: administration method and technology.
An administration method describes how molecular hydrogen reaches the person.
A technology describes how the H₂ is produced, transferred, dissolved, stored, or delivered.
Hydrogen-Rich Water
The administration method is drinking water containing dissolved H₂. That water could be produced by a bottle, pitcher, infusion machine, ionizer, tablet, or commercial beverage.
PEM/SPE Electrolysis
This describes one engineering method used to produce H₂. The resulting H₂ might then be dissolved into water or delivered as gas through an inhalation device.
That distinction is important because two products can use the same administration method while relying on completely different technologies.
Start With the H₂ Administration Methods
H2HUBB’s Molecular Hydrogen Therapy Methods page compares hydrogen-rich water, inhalation, tablets, baths, packaged H₂ water, and specialized clinical or experimental routes.
How Molecular Hydrogen Has Been Administered in Research
One of the useful parts of my original 2017 article was showing that molecular hydrogen research was never limited to one product category.
Researchers have investigated H₂ through multiple administration routes.
Hydrogen-Rich Water
Molecular hydrogen is dissolved into water and consumed orally. This remains one of the most familiar consumer and clinical-research approaches.
Hydrogen Inhalation
H₂ gas is inhaled through an interface such as a nasal cannula, mask, or other research delivery system.
Hydrogen-Rich Saline
Hydrogen can be dissolved into saline for experimental injection or infusion protocols, primarily within research or supervised medical settings.
Hydrogen Baths & Topical Exposure
Hydrogen-rich water can be used for whole-body baths, foot baths, or other topical research applications.
Eye Drops & Localized Delivery
Hydrogen-containing solutions and localized gas-delivery approaches have been investigated experimentally for specific tissues.
Experimental Injection Routes
Animal studies have used intraperitoneal and other injection methods to investigate molecular hydrogen under controlled laboratory conditions.
Research Route Does Not Automatically Equal Consumer Method
Hydrogen-rich saline injection, intravenous infusion, intraperitoneal injection, eye drops, and similar routes appear in scientific research.
They should not be interpreted as DIY consumer administration methods.
For consumers, the most practical H₂ categories are generally hydrogen-rich water, hydrogen inhalation, hydrogen tablets, baths, and packaged hydrogen water.
The Main Consumer Molecular Hydrogen Technologies
This is where the industry has changed dramatically since 2017.
Today, consumers can choose between technologies designed for portability, higher concentration, larger water volumes, continuous availability, inhalation, topical exposure, or simple chemical generation.
The technology itself is only the starting point.
At H2HUBB, the more important question is:
How much usable molecular hydrogen does this specific product actually deliver under realistic conditions?
PEM/SPE Hydrogen Water Technology
PEM stands for proton exchange membrane. SPE stands for solid polymer electrolyte.
In many consumer H₂ products, those terms describe the same general family of membrane-based electrolysis technology.
A PEM/SPE cell separates the oxygen-producing side of electrolysis from the hydrogen-producing side.
On the oxygen side, water is oxidized. Protons travel across the membrane, electrons travel through the electrical circuit, and molecular hydrogen forms at the cathode.
One advantage of PEM/SPE architecture is that the hydrogen and oxygen-production zones can be physically separated.
But seeing “PEM” in a product description does not automatically tell you:
- how much H₂ it produces,
- how efficiently the H₂ dissolves,
- how long the membrane will last,
- whether the product water remains appropriately isolated,
- or whether the final product meets H2HUBB’s standards.
Want the Technical Electrochemistry?
Our technical H2 Basics guide explains PEM/SPE electrolysis, electrode reactions, source-water chemistry, gas transfer, hydrogen tablets, water ionizers, and dissolved-H₂ measurement.
Portable Hydrogen Water Bottles
Portable hydrogen water generators are one of the biggest changes between the market I was describing in 2017 and the market we have today.
Modern bottles commonly use PEM/SPE technology inside a sealed water chamber.
The cell generates hydrogen gas, and the bottle design attempts to dissolve that H₂ into a relatively small water volume.
Small Water Volume
Many bottles hold roughly 250–500 mL, allowing relatively high concentrations to translate into meaningful H₂ doses in one serving.
Pressure
Sealed bottles can use elevated internal hydrogen pressure to increase the amount of H₂ that remains dissolved in the water.
Cycle Time
Modern cycles can range from several minutes to around 20 minutes, depending on product design and target concentration.
Real Performance
Two bottles using PEM/SPE technology can produce dramatically different dissolved-H₂ concentrations and total H₂ doses.
H2HUBB’s current qualification standard for portable hydrogen-water generators requires:
- PEM/SPE cell architecture,
- no detectable chlorine contamination during applicable testing,
- no detectable ozone contamination during applicable testing,
- a cycle no longer than 20 minutes,
- and at least 0.8 mg of H₂ within a practical daily serving pattern not exceeding 1 liter of water.
Dedicated Hydrogen Infusion Systems
Dedicated hydrogen infusion systems take a different approach.
Instead of treating the drinking water itself as the electrolysis electrolyte, a system may generate pure H₂ separately and then transfer that hydrogen gas into filtered product water.
I like this architecture conceptually because it lets engineers separate two problems:
Problem #1: Produce H₂
Engineer the electrolysis system specifically around reliable hydrogen-gas generation.
Problem #2: Dissolve H₂
Engineer the drinking-water side specifically around gas transfer, mixing, bubble size, contact time, pressure, recirculation, flow, and retention.
This is why a product’s gas-production rate is not enough by itself.
A machine can generate a lot of H₂ and still produce mediocre hydrogen water if the gas-transfer system is inefficient.
Pressurized Hydrogen Water Systems
Pressurized systems use hydrogen partial pressure to increase the amount of H₂ that can dissolve into water.
This can be done through:
- sealed batch chambers,
- pressurized recirculation loops,
- sealed portable bottles,
- or other engineered gas-transfer systems.
Pressure is particularly useful because the commonly cited approximately 1.6 mg/L saturation value for molecular hydrogen applies only to particular temperature and pressure conditions.
Increase hydrogen partial pressure or lower the water temperature, and higher dissolved-H₂ concentrations become physically possible.
A well-designed system therefore combines:
Water Ionizers and Electrolyzed Reduced Water
Water ionizers were one of the dominant hydrogen-water technologies when I wrote the original article.
They remain part of the hydrogen-water category, but I would describe them differently today.
Traditional water ionizers use electrolysis to separate the incoming water into:
- a cathodic, reduced stream, and
- an anodic, oxidized stream.
Molecular hydrogen can be generated in the cathodic water.
But the original purpose of many legacy ionizers was strongly centered around alkaline water and pH separation, rather than optimizing dissolved-H₂ dose as the primary engineering objective.
pH Is Not a Measurement of Molecular Hydrogen
This is one of the most important corrections consumers need to understand.
A water pH of 9, 9.5, or 10 does not tell you how much H₂ is dissolved in that water.
Likewise, ORP can respond to dissolved hydrogen but should not be used as a substitute for directly measuring dissolved H₂.
If the therapeutic interest is molecular hydrogen, measure molecular hydrogen.
H2 output from a water ionizer can also depend heavily on:
- source-water mineral content,
- conductivity,
- flow rate,
- electrode surface area,
- electrical current,
- pH setting,
- and cell condition.
That means the same ionizer can behave differently with different source water or operating conditions.
Hydrogen Water Tablets
Hydrogen tablets use chemistry instead of an electrical generator.
Many modern H₂ tablets use elemental magnesium combined with acids and other formulation ingredients.
A simplified magnesium-water reaction is:
The formulation can be designed to control reaction speed and help prevent the magnesium surface from becoming passivated too quickly.
Tablets have several practical advantages:
- no electricity,
- very portable,
- little equipment,
- and some products can produce several milligrams of H₂ from a single tablet.
But tablet performance depends heavily on how the product is prepared.
Water Volume
The same total H₂ production creates a very different mg/L concentration in 250 mL versus 500 mL.
Container
Pressure, sealing, headspace, and gas permeability influence how much H₂ remains in the water.
Reaction Time
Drinking too early can mean the reaction is incomplete. Waiting too long after opening can allow H₂ to dissipate.
Formulation
Magnesium amount, acid blend, binders, dissolution behavior, and tablet chemistry all influence real-world H₂ production.
This is why the ingredient list alone cannot tell you the delivered H₂ dose.
The finished hydrogen-rich water needs to be measured under a defined preparation protocol.
Ready-to-Drink and Packaged Hydrogen Water
Prepackaged hydrogen water eliminates the need to generate H₂ immediately before every serving.
But it creates a completely different engineering challenge:
keeping an extremely small gas molecule inside the package.
Hydrogen can escape from water and through some packaging materials over time.
That means packaged hydrogen-water performance depends on:
- packaging material,
- barrier layers,
- closure integrity,
- headspace composition,
- filling pressure,
- storage temperature,
- and time since packaging.
Aluminum cans and appropriate multilayer packaging can provide better hydrogen retention than more gas-permeable packaging.
But I would still want to see actual shelf-life testing rather than assuming the package retains its original H₂ concentration forever.
Hydrogen Inhalation Technology
The original 2017 article described hydrogen inhalation as water electrolysis producing H₂ and O₂ together while keeping hydrogen below 4%.
That description is too narrow for the modern market.
Today’s inhalation systems fall into several categories.
Pure H₂ Systems
PEM/SPE electrolysis can separate oxygen production from the hydrogen stream and provide high-purity H₂ gas for delivery through a nasal cannula or other interface.
Oxyhydrogen Systems
Other electrolyzers intentionally deliver hydrogen and oxygen together, often in an approximately 2:1 hydrogen-to-oxygen production ratio dictated by water electrolysis.
The key point is that the source-gas percentage is not necessarily the same as the H₂ concentration a person actually inhales.
A nasal cannula delivering pure hydrogen mixes the H₂ stream with room air as the person breathes.
So at H2HUBB, we look at:
- actual H₂ flow in mL/min,
- gas composition and purity,
- the delivery interface,
- the user’s breathing conditions,
- estimated or measured inhaled H₂ concentration,
- filtration,
- and appropriate device safety systems.
Hydrogen Inhalation Needs Its Own Guide
Hydrogen flow, breathing rate, inhaled H₂ concentration, pure-H₂ versus oxyhydrogen systems, safety, and research dosing require more explanation than we can give them in a general technology article.
The Number That Connects Hydrogen Water Technology to the Consumer: H₂ Dose
This is one part of the original article that I absolutely want to keep.
Molecular hydrogen dissolved in water is commonly reported in mg/L.
For dilute aqueous H₂, mg/L is numerically close to ppm by mass.
But mg/L is a concentration—not the total amount of molecular hydrogen in the serving.
Here are a few simple examples:
0.5 mg/L × 1 L
Approximately 0.5 mg H₂.
1 mg/L × 1 L
Approximately 1 mg H₂.
5 mg/L × 300 mL
Approximately 1.5 mg H₂.
10 mg/L × 300 mL
Approximately 3 mg H₂.
This explains why a modern high-concentration portable bottle can sometimes provide more H₂ in 300 mL than an older hydrogen-water device produces in an entire liter.
What About the 1–3 mg H₂ Target?
In the original article, I referred to approximately 1–3 mg of H₂ per day.
We still use that range at H2HUBB, but I want to be precise about what it means.
Approximately 1–3 mg H₂/day is a commonly referenced practical target based on amounts of molecular hydrogen administered across a broad range of human clinical studies.
It is not a universal standard or a proven optimal dose for every person.
When looking more broadly across human hydrogen-water research and the modern higher-performing consumer market, approximately 1–15 mg H₂/day can be used as a wider research-informed reference range.
The reason this matters in a technology article is simple:
A hydrogen-water technology becomes more useful when it can deliver the amount of H₂ you are trying to consume without requiring an unrealistic amount of water.
Calculate Total H₂ Instead of Comparing ppm Alone
Enter hydrogen concentration and water volume into the H2HUBB calculator to estimate the milligrams of molecular hydrogen contained in a serving.
Not All Hydrogen Water Devices Are Created Equal
That heading came directly from the original article, and I still believe it is one of the most important things a consumer can understand.
Two products may both say:
“PEM/SPE hydrogen water generator.”
Yet one may produce 1 mg/L while another produces 8 mg/L.
One may make that concentration consistently. Another may advertise only its highest laboratory peak.
One may deliver 0.3 mg per serving. Another may deliver 2 or 3 mg.
One may use appropriate water isolation and gas management. Another may be poorly engineered.
The technology name does not answer those questions.
How H2HUBB Evaluates the Complete Product
- Measure actual dissolved H₂ or gas output.
- Look at average and repeatable performance—not only peak numbers.
- Calculate total H₂ dose from concentration and serving volume.
- Evaluate practical cycle time or dispensing performance.
- Consider PEM/SPE architecture and gas separation where applicable.
- Evaluate chlorine, ozone, gas purity, filtration, electrolytes, pressure, or other category-specific safety issues where relevant.
- Consider product maintenance, source-water requirements, warranty, and real-world usability.
This is why H2HUBB uses category-specific performance standards.
A portable bottle should not be evaluated exactly like a water ionizer. A hydrogen tablet should not be evaluated like a pitcher. A bath product should not be evaluated like an inhalation machine.
Different technologies have different engineering limits, practical uses, and safety considerations.
See the Standards Behind H2HUBB Approval
H2HUBB publishes minimum performance and safety criteria for hydrogen infusion systems, portable bottles, pressurized systems, tablets, water ionizers, pitchers, packaged water, inhalation devices, baths, and other H₂ categories.
An Important FDA / GRAS Clarification From the Original Article
What I Wrote in 2017
The original article described molecular hydrogen as having been “approved by the FDA as a supplement.”
I would not use that wording today.
The more accurate regulatory context is FDA GRAS Notice No. 520.
GRAS means Generally Recognized as Safe.
The notice concerned the intended use of hydrogen gas as an ingredient in drinking water, flavored beverages, and soda drinks at specified conditions of use.
FDA responded that it had “no questions” regarding the notifier’s GRAS conclusion.
That is not the same thing as FDA approving molecular hydrogen as:
- a drug,
- a medical treatment,
- a cure for disease,
- or a universally approved dietary supplement therapy.
I think that distinction is important because regulatory language should be just as accurate as scientific language.
Where This Article Fits in H2HUBB’s 2026 Education System
H2HUBB now has enough educational material that this article does not need to explain every scientific administration route or every electrochemical reaction by itself.
I see these pages as three different layers:
Molecular Hydrogen Therapy Methods
Start here to understand the major administration routes: hydrogen water, inhalation, tablets, baths, packaged water, and specialized research routes.
Hydrogen Water Technologies
This article. Use it to understand the major consumer technologies and why products using similar technology can still perform very differently.
How Hydrogen Water Is Made
Go deeper into PEM/SPE electrochemistry, water ionizers, hydrogen tablets, gas-transfer systems, source-water chemistry, and dissolved-H₂ measurement.
Method tells you how H₂ reaches the body. Technology tells you how the product creates or delivers it. Testing tells you whether that particular product actually performs.
The H2HUBB Position in 2026
When I wrote this article in 2017, the hydrogen industry was still trying to teach consumers that molecular hydrogen was even the important part of hydrogen water.
Today, I think we can ask much better questions.
Instead of:
“Does this make hydrogen water?”
I want to know:
- How much H₂ does it produce?
- How much actually dissolves?
- How much H₂ is in one serving?
- How repeatable is the performance?
- How quickly does H₂ dissipate?
- What technology is being used?
- Does the system introduce any unwanted byproducts?
- Does it work with the water the consumer will actually use?
- How difficult is it to maintain?
- And has someone independent of the manufacturer actually tested it?
That is how the hydrogen industry moves from interesting technology to qualified technology.
Compare Qualified Hydrogen Technologies
H2HUBB organizes independently evaluated hydrogen products by technology and delivery category so you can compare measured performance, product type, current pricing, available discounts, and how each system is intended to be used.
Frequently Asked Questions
What are the main hydrogen water technologies?
Common hydrogen-water technologies include PEM/SPE portable generators, hydrogen infusion systems, pressurized dissolution systems, reservoir pitchers, water ionizers, magnesium-based hydrogen tablets, and packaged hydrogen-rich water.
These technologies can all produce hydrogen-rich water, but their concentration, total H₂ dose, cycle time, water requirements, and real-world performance can differ substantially.
What is PEM/SPE hydrogen technology?
PEM means proton exchange membrane and SPE means solid polymer electrolyte. In many hydrogen products, these terms describe membrane electrolysis that physically separates the hydrogen- and oxygen-production sides of the electrochemical cell.
The generated H₂ can then be dissolved into water or delivered as gas.
Is alkaline water the same as hydrogen water?
No. Alkaline pH and dissolved molecular hydrogen are separate characteristics.
Some electrolyzed reduced water contains both elevated pH and dissolved H₂, but pH does not tell you how much hydrogen is present.
Are hydrogen water bottles better than water ionizers?
Not automatically.
Modern PEM/SPE bottles are often specifically engineered around high dissolved-H₂ concentration in small servings, while water ionizers can provide larger volumes of electrolyzed water.
The better comparison is measured H₂ performance, total dose, convenience, source-water requirements, maintenance, price, and how the consumer plans to use the product.
How do hydrogen tablets make H₂?
Many hydrogen tablets use elemental magnesium together with acids and other formulation ingredients.
Magnesium reacts in water to generate molecular hydrogen. Final H₂ concentration depends on formulation, water volume, container design, temperature, pressure, and reaction time.
Is 1.6 mg/L the maximum possible hydrogen concentration in water?
No. Approximately 1.6 mg/L is a useful saturation reference near room temperature and approximately one atmosphere of H₂ pressure.
Higher H₂ partial pressure and lower temperature can allow considerably more molecular hydrogen to remain dissolved. This is one reason pressurized hydrogen-water systems can exceed the normal atmospheric saturation concentration.
How much H₂ should hydrogen water provide?
H2HUBB uses category-specific product standards rather than one universal number for every product.
For consumer intake, approximately 1–3 mg of H₂ per day is commonly referenced as a practical research-informed target based on amounts administered across a broad range of human studies.
Approximately 1–15 mg/day represents a broader research-informed range encountered across hydrogen-water research and modern higher-performing consumer products.
These are reference ranges, not universal dosing standards.
Is molecular hydrogen FDA approved?
It is more accurate to say that FDA GRAS Notice No. 520 covers hydrogen gas for specified use as an ingredient in drinking water, flavored beverages, and soda drinks, and FDA issued a “no questions” response to that GRAS notice.
That should not be described as FDA approval of molecular hydrogen as a drug, treatment, cure, or universal dietary supplement therapy.
How should I compare hydrogen products using the same technology?
Compare directly measured H₂ output, average performance, total dose per serving, water volume, cycle time, source-water requirements, safety controls, maintenance, warranty, price, and independent testing.
The technology name alone is not enough to determine product quality.
H2HUBB Safety Note
Consumer hydrogen-water products and research administration routes are not interchangeable.
Injection, infusion, eye-drop, and other specialized experimental methods should not be recreated as DIY hydrogen-delivery methods.
Hydrogen inhalation also requires appropriate device design, gas handling, filtration, delivery, and safety considerations.
References & H2HUBB Resources
- Molecular Hydrogen Therapy Methods — H2HUBB
- How Hydrogen Water Is Made: Electrolysis & H₂ Technology
- H2HUBB Product Performance Standards
- H2HUBB Hydrogen Product Collections
- H2HUBB Hydrogen Water Collection
- H2HUBB Hydrogen Inhalation Therapy Guide
- H2HUBB Hydrogen Dose Calculator
- H2HUBB Molecular Hydrogen Research Library
- Ohta S. Molecular hydrogen as a preventive and therapeutic medical gas: initiation, development and potential of hydrogen medicine. Pharmacology & Therapeutics. 2014.
- Convenient methods for ingestion of molecular hydrogen: drinking, injection, and inhalation. View Study
- U.S. FDA GRAS Notice No. 520 — Hydrogen Gas. View FDA Record