Oxygenated water is a controversial thing.
Many claim it has no benefits over mere tap water. That there’s no science behind ingested oxygen. That oxygen water is a scam, similar to homeopathy.
Meanwhile, some oxygen water companies claim their product to be an elixir—a potent magical drink that enhances exercise performance beyond your wildest dreams.
So what should we believe about oxygenated water? Let's focus on the science: ingested oxygen might not boost your performance, but there are clinical trials suggesting other health benefits from drinking dissolved O2.
The research is young—yes—but the data that does exist should prompt researchers to run more studies on oxygenated water.
In this article, you’ll learn the current state of oxygen water science: animal studies, human studies, and what’s still missing from the equation.
But before we dive into the data, let’s cover some basics about oxygen.
Why You Need Oxygen
Oxygen (O) is the third most abundant element in the Universe. When you stick two oxygen atoms together, you get O2.
This molecule, also called oxygen, is essential to human life. For our purposes here, “oxygen” will refer to O2.
Let’s talk about breathing. The main reason you breathe is to gather oxygen and expel carbon dioxide (CO2) from your body. When you inhale, oxygen fills your lungs—and tiny sacs called alveoli diffuse this precious gas into your bloodstream.
Once circulating, your cells use oxygen to make usable energy (ATP) through a process called cellular respiration.(1) More specifically:
• Oxygen is required for glycolysis, or for turning glucose into energy
• Oxygen helps build the electron transport chain, which keeps energy production flowing in your body
Without oxygen, your cells quickly run out of energy, leading to cell death. Again, oxygen is essential to human life.
To hammer this home, hold your breath for about thirty seconds, and see how rapidly your priorities shift.
Overrides everything else, doesn’t it?
The truth is, humans can go for days or weeks without food. But deprive a person of oxygen for more than a few minutes and … well, you can guess the result of that little experiment.
Okay, let’s get to the fun stuff now. Oxygenated water.
What Is Oxygenated Water?
Oxygenated water is water infused with additional oxygen. Simple enough. Kind of like carbonated water but with a different gas.
All water—tap water included—contains some dissolved oxygen. This oxygen is not the oxygen from H2O, but rather dissolved O2 itself.
In fact, the dissolved oxygen content of a natural water source is a good indicator of its water quality. Believe it or not, aquatic organisms rely on dissolved oxygen to sustain themselves.(2)
This is dreadfully clear in the “dead zones” that cover huge swaths of the Gulf of Mexico. Very little dissolved O2, very little life.
Commercially available oxygenated water, on the other hand, is a manmade creation—and generally contains at least five times the oxygen of drinking water. Specifically, oxygenated water contains anywhere from 30 to 120 mg / L dissolved oxygen content.(3)
You may have heard that oxygen water improves exercise performance, blood oxygen levels, recovery, and detoxification. Some of these claims have data behind them, others don’t.
We’ll get there soon. First, though, let’s address the most common criticism of oxygen water.
Does Ingested Oxygen Get Absorbed?
Critics of oxygen water give a hard NO to this question. They say oxygen molecules can’t diffuse across your GI tract and enter your bloodstream.
But evidence suggests otherwise. In one 2001 study, large doses of ingested oxygen did end up in the blood of 15 lucky rabbits.(4)
How? Via the portal vein.
The portal vein, by the way, is a massive blood vessel that carries blood from your gut, pancreas, and spleen to your liver. About 75% of blood flow to your liver comes through the portal vein.(5)
Here’s how it works:
• You eat or drink something
• The food is broken down into nutrients and toxins in your mouth, stomach, intestines, etc. (all along your GI tract)
• Some nutrients and toxins travel across the gut barrier and are carried—via the portal vein—to your liver
• Your liver decides what to do with these molecules (methylate them, burn for energy, send back to bloodstream, etc.)(5)
Granted, this an oversimplification. But it’s more or less how ingested molecules arrive in your bloodstream.
Remember: in rabbits, dissolved oxygen did reach the bloodstream through the portal vein pathway. But human evidence is less clear. Most human studies, in fact, show no change in blood oxygen levels from drinking oxygen water.(6)
But this doesn’t prove oxygen doesn’t reach the liver. It only implies that blood oxygen levels aren’t meaningfully affected by drinking dissolved oxygen.
And based on other metrics, several human studies suggest that ingested O2 does reach the liver. Keep reading.
Potential Benefits of Oxygenated Water
Oxygen water enhances exercise—and other such claims—have caught plenty of flack.
This flack is mostly deserved. Researchers have found, in several randomized controlled trials, that oxygenated water neither boosts oxygen saturation (% oxygen in the blood) nor exercise performance in athletic populations.(6)
There’s stronger evidence, however, for two other benefits.
#1: Exercise Recovery
Along with glucose and oxygen, your body also uses a molecule called lactate (or lactic acid) to make energy. Your muscles maintain a stable supply of lactate through a steady eb of production and clearance.
But when you exercise intensely, lactate production skyrockets—and lactic acid builds up in your muscles faster than you can clear it. This buildup of muscle lactate is, in part, responsible for exercise-induced fatigue.
But get this. When you improve lactate clearance, you also improve exercise recovery.(6)
That’s where oxygenated water comes in.
In a double blind, placebo-controlled, crossover study design, researchers gave 25 trained runners several doses of oxygenated water (or placebo) before, during, and after a 5000 meter time trial.(6) The results were interesting.
“Despite no evidence of improved exercise performance,” write the authors, “ingestion of [oxygenated water] did enhance post-exercise recovery via increased lactate clearance.”
Why might O2 water improve lactate clearance? By helping the liver do its job better.
Yes, your liver helps you clear excess lactate. The researchers speculated that getting more oxygen to the liver (by drinking O2 water) may have enhanced lactate clearance in the 25 runners.
And so, based on this result, oxygenated water is a promising recovery drink.
#2: Alcohol Clearance
Besides lactate, what else does the liver help clear? That’s right, alcohol.
Your liver treats alcohol (or ethanol) like a toxin. Here’s how your liver “detoxifies” this toxin (7):
• When you ingest alcohol, it travels through the gut and into your liver via the portal vein
• Your liver uses an enzyme called alcohol dehydrogenase to convert ethanol to acetaldehyde
• Acetaldehyde is converted to acetate via other liver enzymes
• Acetate is converted to water and carbon for easy disposal
The theory is: drinking oxygenated water delivers more O2 to the liver, and should help your liver oxidize (detoxify) alcohol more efficiently.
This theory has been tested.
Here’s the study setup. Fifteen healthy men were randomized to three conditions: normal alcohol with normal water, oxygenated alcohol with normal water, and oxygenated alcohol with oxygenated water. Each consumed about half a liter of a 20% alcoholic beverage (excessive drinking), along with their normal or oxygenated water.(3)
The punchline? Those in the third group (oxygenated alcohol with oxygenated water) saw the fastest decline to a 0.05% BAC. Significantly faster than the first group.
Oxygenated Water Recap
Okay, that was a lot of info. Here are the key takeaways:
• Oxygen is essential to human life. Without it, your cells would swiftly perish.
• Animal evidence suggests that drinking oxygenated water brings O2 to the bloodstream via the portal vein.
• Oxygen water may enhance certain aspects of liver function through increased liver oxygenation.
• Most evidence suggests that oxygenated water does not increase blood O2 levels or boost exercise performance in humans.
• Ingesting oxygen may help with exercise recovery by increasing lactate clearance.
• Drinking oxygen water has been shown to accelerate alcohol clearance after excessive boozing.
Oxygenated water is a charged topic, but hopefully this article helped you separate fact from fiction.
One last experiment? Try O2 water for yourself, and see what it does for you.