Yes, exactly, and those are called free radicals. So thanks for agreeing with me, I guess. I don't know why that explanation was needed since it proves my point.because H₂O₂ is a side product of many oxidase enzymes that use O₂ as an oxidant...
Where háve I claimed that antioxidants treat diseases? What a massive straw man. My point was that, since the body naturally produces extremely powerful antioxidants, that tells us that the body doesen't want large amounts of free radicals around. While the body does use reactive oxygen species for cell signaling and you would die if you reduce it to zero, large amounts are extremely harmful and implicated in the etiology of many diseases.antioxidants do not treat disease, otherwise you'd see people prescribing e.g. methylene blue for viral/bacterial infections
As for antioxidants in diet not treating diseases that have a strong oxidant load, like Parkinson's and asthma, which is what you seem to be accusing me of claiming, that is not a good argument because most antioxidants from the diet like vitamin C, E, quercetin, etc, are very weak and/or so poorly absorbed that it will have no effect in cells. But that does not mean that oxidation in excesso is not harmful.
And BTW, just because something does not treat diseases it does not mean that it does not prevent diseases. For instance, a low sugar diet does not cure diabetes, but it can prevent you from becoming diabetic in the first place. Eating lots of produce and fruits does not treat cancer, but it might stop you from developing câncer in the first place.(especially intestinal câncer). While the phytohemicals in plants have extremely poor bioavailability, the metabolism generates uric acid which does have antioxidante properties on many cells. The lower rate of cancer among vegetarians that eat lots of produce indicates that antioxidants might be valuable in preventing diseases.