How much of the oxygen in our bodies comes from water?


65% of our body is oxygen and 60%-90% of our body is water, so how much of that 65% oxygen is from water?

In: Biology

The vast majority of it. Smaller amounts come from the various proteins, carbs, and vitamins we eat, and even more from the air we breathe, simply because oxygen is a good molecule for making chemical bonds. But because we have so much water in our bodies, we also have an absolutely huge amount of oxygen.

Most of it. Oxygen is found in a lot of organic molecules, but only in comparatively small amounts next to the far more abundant carbon and hydrogens. On the other hand, it makes up almost all of the mass of water (32/34ths of it). And of course a some of it is dissolved in our bloodstream and tissues as molecular oxygen.