Hydrogen Water Benefits: What the Studies Show So Far

What is hydrogen water?

Hydrogen water, also called hydrogen-rich water, is ordinary water with extra molecular hydrogen gas (H2) dissolved in it. Every water molecule already contains hydrogen atoms; what's added here is the gas itself, which researchers are studying as a possible antioxidant.

A 2024 systematic review in the International Journal of Molecular Sciences describes how it's made: by dissolving hydrogen gas into water under pressure, or with hydrogen-generating tablets, infusion machines, water generators and ionizers. Hydrogen molecules are tiny and can stay dissolved for a while, the review explains, but the amount of hydrogen varies between products and studies, which makes results hard to compare.

Why researchers think hydrogen might help

The interest comes from oxidative stress. Your body makes reactive oxygen species as it uses oxygen, and the 2024 review links an excess of them to lifestyle-related diseases and aging. Hydrogen is thought to neutralize some of the most reactive of these molecules and to switch on the body's own antioxidant defenses, and it has shown anti-inflammatory effects in lab and early human studies.

The same review is careful to add that the exact mechanism is poorly understood. A plausible mechanism is a reason to run trials, not proof of a benefit, which is why the human studies below matter more.

Hydrogen water benefits: what the research shows

Most research on hydrogen water is recent, small and short. These are the systematic reviews and meta-analyses we found on PubMed, and what each one concluded:

Each review is listed in Sources. None of these studies tested a specific consumer bottle or device.

The 2024 systematic review is frank about the weak spots: many studies were done in animals, some human trials were small, most looked only at short-term effects, some had no placebo group, and some may have been backed by organizations with an interest in hydrogen water products. Its authors call for larger, longer, well-designed human trials.

The cholesterol meta-analysis goes further, saying its results shouldn't justify routine use of hydrogen water to lower lipids outside research. And if your goal is fitness, the training does the heavy lifting; our guide to health-related fitness covers what to work on.

Is hydrogen water good for you?

It's water, so it hydrates you like any other water, and the early safety picture is reassuring. The 2024 systematic review describes hydrogen-rich water as mostly considered safe, with no to minimal side effects. In 2014 the FDA responded with no questions to a company's notice concluding that hydrogen gas is generally recognized as safe (GRAS) as an ingredient in drinking water, flavored drinks and soda, at up to 2.14% by volume. That's a food-safety notice, not an FDA approval of any health claim.

What isn't established is that it does more for your health than plain water. Long-term effects haven't been studied much, and the benefits seen so far are small. If you have a health condition, hydrogen water isn't a substitute for treatment, and you shouldn't stop or change a medicine because of it.

Hydrogen water vs. plain water: is it worth it?

Plain tap water is cheap and does the main job, keeping you hydrated. Hydrogen water adds a gas with promising but small effects in short studies. Whether that's worth the extra cost is a personal call; nothing in the research makes it necessary.

If you're curious and want to make it at home, look for a product that states how much hydrogen ends up in the water. Without that number, you can't compare it with the amounts used in studies. We reviewed the LifeWater Hydrogen Bottle, a rechargeable glass bottle that runs a 3-minute electrolysis cycle. The brand doesn't publish the hydrogen concentration, and no study has tested the bottle itself, so see it as an easy way to make hydrogen water and enjoy your daily water, not as a fix for a health problem.

• Keep your expectations in line with the evidence: possible small effects, not a cure.
• Check what the seller publishes: the hydrogen level, what the bottle is made of, and the return terms.
• Tell your doctor if you're drinking it while being treated for a condition such as liver disease or high cholesterol.
• Count it toward your daily fluids, just like plain water.

How much water do you need?

There's no single number for everyone. In its 2004 report on water and electrolytes, the National Academies set reference levels based on what adequately hydrated people actually take in: about 2.7 liters (91 ounces) of total water a day for women and about 3.7 liters (125 ounces) for men. Total water means everything: plain water, other drinks, including ones with caffeine, and the water in food. For a full breakdown by age, heat and exercise, read how much water you should drink a day.

Cups are 8 fl oz. The drink figures are our math from the report's estimate that about 80% of total water comes from beverages and about 20% from food.

The panel deliberately gave no rule of thumb for glasses per day. It concluded that most healthy people meet their needs by letting thirst be their guide, and that very active people who are often in hot weather can need 6 liters or more.

MedlinePlus adds that you should drink more when it's hot or you're exercising, and pay attention to fluids when someone has a fever, vomiting or diarrhea. Older adults and people with diabetes are at higher risk of dehydration.

When to see a doctor

Hydrogen water isn't a treatment, so see your doctor about any symptom you're hoping it will fix. And because it's still water, know the signs of dehydration. MedlinePlus lists these signs of severe dehydration:

• Not urinating, or very dark yellow or amber urine
• Dry, shriveled skin
• Irritability or confusion
• Dizziness or lightheadedness
• Rapid heartbeat or rapid breathing
• Sunken eyes or listlessness

Call 911 if someone loses consciousness, becomes confused or has a seizure, has a fever over 102°F (38.8°C), shows signs of heatstroke such as a rapid pulse or rapid breathing, or doesn't improve despite treatment (MedlinePlus).

If you have kidney, heart or liver disease, or your doctor has limited how much you drink, ask before changing your fluid intake. And if you're drinking hydrogen water hoping to improve a number such as cholesterol or blood pressure, track that number with your doctor; our guide to blood pressure by age shows how to measure at home.

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