Hydrogen Water Explained
Hydrogen water is simply water with molecular hydrogen gas (H₂) dissolved in it. H₂ is colorless, tasteless, and odorless. Water ionizers produce it naturally at the negative electrode during electrolysis, so the alkaline water they make is also hydrogen-rich when it first comes out of the faucet.
Why hydrogen is getting attention
Interest in molecular hydrogen grew after a 2007 study in Nature Medicine (Ohsawa et al.) reported that H₂ acted as a selective antioxidant in cell and animal models. Since then, researchers have registered dozens of human clinical trials. A 2023 review in Molecules identified 81 registered clinical trials and 64 published human studies on hydrogen, across areas such as exercise, metabolic health, and inflammation.
What we can say, and what we can't
- The research is active and early results are described by reviewers as "encouraging."
- Most human studies are small and short, and many findings come from animal studies. A 2024 systematic review in the International Journal of Molecular Sciences concluded that larger, long-term human trials are still needed.
- Hydrogen water has not been shown to treat or prevent any disease, and we do not make those claims.
See the full list of sources on our Research & Studies page.
Getting the most hydrogen from your water
- Drink it fresh. H₂ is the smallest molecule and escapes from water over time, especially in open glasses, warm water, or when stirred. Drink within minutes for the highest levels.
- Use a closed container. If you carry water with you, a full, tightly sealed bottle holds hydrogen better than a half-empty one.
- Measure it properly. Ask for dissolved-hydrogen figures in ppm or ppb, measured with a dedicated H₂ meter or titration reagent. ORP readings do not measure hydrogen content.
Ionizers vs. other hydrogen sources
Hydrogen water can also come from portable hydrogen bottles, tablets, or pre-filled cans and pouches. An ionizer makes it on demand from your filtered tap water, in larger volumes, for the whole household. See The H2 Advantage for a side-by-side comparison.
Questions before you buy?
Our team can help you compare models for your water, household, and budget. Contact us or browse countertop, under-sink, and commercial ionizers.
This page is for general education and is not medical advice. Water ionizers are drinking-water appliances; they are not intended to diagnose, treat, cure, or prevent any disease. If you have kidney disease, take medications that affect potassium, or have another medical condition, talk with your doctor before changing what you drink.