Oxygen is critical for life and that also makes is susceptible to chicanery. If oxygen is so essential that the brain is permanently injured after just four minutes of deprivation, then surely more must be better! That’s the argument used by sellers of “oxygenated water” who often target athletes with claims that their product can improve athletic performance. Well, all water is actually oxygenated water because oxygen from the air dissolves in water, although not to a great extent since its solubility is only about 25 mL per liter. Still, this is enough for fish to extract with their gills to sustain life. More oxygen can be squeezed into water under pressure, which is exactly what the “oxygenated water” people do. However, most of this oxygen escapes into the air as soon as the pressure is released by opening the bottle.
Whatever dissolved oxygen remains is inconsequential since we do not breathe through our gut. Only a trace of the trivial amount of oxygen in the water will pass through the intestinal lining into the bloodstream, which is already saturated with oxygen anyway. The most salient point is that a single breath of air contains more oxygen than a liter of oxygenated water. A single breath is about 500 mL of air, of which is roughly 20% or 100 mL is oxygen. A sampling of a variety of oxygenated waters reveals an average of about 10 mL oxygen per 100 ml of water. Clearly, even if the oxygen from the water were absorbed, it would be less than taking an extra breath.
Of course, in science we do not go by theory, but by experimental evidence. And a number of studies clearly show that drinking oxygenated water has no effect on any sort of performance. Subjects performing standard maximal cardiopulmonary exercise tests drank either regular water or oxygenated water and there were no significant differences in results. Furthermore, participants were unable to identify the type of water they had consumed.
Often there is even more absurd hype piled on oxygenated water. There are claims that the oxygen content of the atmosphere is decreasing due to pollution, so we must supplement our intake with “superoxygenated water.” Total nonsense. Then there are these stupefying statements: “The oxygen is stabilized in micro-encapsulated water clusters.” “Our patented method of expansion and contraction of the water molecules several times per minute allows more oxygen consumption while taking on donor electrons.” “We use monoatomic oxygen in addition to other salutary forms of oxygen: O2, O4, O5, O6 and O7 which is less than half the diameter of regular diatomic oxygen.” Absolute mind-boggling gobbledigook!
For the cherry on top, these oxygenated waters are often sold in health food stores in an aisle next to dozens of types of antioxidants that claim to confer eternal health by neutralizing those dastardly free radicals generated by the body’s use of oxygen. I hope we have now thrown enough cold water on the hot hype of oxygenated water.