Please remember to spread the word about this :(

https://lemmy.today/post/32285865

On the topic, as oxidation is a pretty prevalent negative side effect of living, our body has multiple mechanisms to deal with it, no? So my question is: where do the "antioxidants" that we can eat come into the picture here? Are they like preventing oxidation from even occurring, or are they like the shields that our cells use to protect themselves from oxidative stress, or what have you?

Oxidation is how red blood cells collect oxygen to pass to the rest of the body. In fact it is iron in hemoglobin that “rusts” to collect the oxygen.

Antioxidants have nothing to do with this.

The process you’re thinking of is oxygenation, not oxidation. Oxygenation is the binding of oxygen to other molecules, oxidation is the loss of electrons. When the iron in hemoglobin oxidizes (from Fe2+ to Fe3+) it stops binding with oxygen, and if it oxidizes further (to Fe4+) it can start oxidizing other molecules in your body. Your body has enzymes to reduce the iron back to a reactive state, but antioxidants also play a role in reducing oxidized molecules.

It’s actually the opposite. When the oxygen binds to the iron it changes from Fe+2 to Fe+3 so the binding of oxygen to the iron in hemoglobin is an oxidation process. At that point it can’t take more oxygen until it releases it in a reduction reaction.

The term “oxidation” is originally derived from reactions where a substance combines with oxygen but has since been generalized to any reaction where an electron is given up. So “oxidation” is the broader term and “oxygenation” is the specific oxidation reaction that results in binding oxygen.