But how do you know the effect isn't from the bromelain? There are studies looking at antiinflammatory effects of bromelain.

If you look at something like lipoic acid--sure it's an antioxidant, but it also serves a vitamin-like function--if we couldn't make our own, there would likely be a dietary requirement. Same with CoQ10. Vitamin c and beta carotene--functions in the body that go beyond just reducing oxidative stress. A lot of the time the benefit from these antioxidants is enzyme mediated, it's not just about reduction vs. oxidation, controlled reduction and oxidation is crucial. So if quercetin helps you, there's still the question of why, what metabolic pathways specifically might it interact with.

I do think there's a problem with lumping in antioxidants as a class, sort of like the problem with the whole acid/alkaline diet thing. Sure we need some alkaline nutrients. But it makes more sense to look at our need for potassium, sodium, magnesium, calcium etc. as individual nutrients rather than as a class of nutrients.

A lot of the phytonutrient studies in rodents that show promise use crazy high doses. The amount of wine you'd have to drink to match the resveratrol given to mice is beyond human capacity, Blueberry studies use the peel or leaf extracts, allowing for doses far beyond what you can get eating blueberries. Studies show pharmacological effects at pharmacological doses, then people use these as evidence that they should wash down blueberries with red wine, when the effectiveness depends on homeopathic doses of the relevant metabolites. I read an article the other day on Flex magazine suggesting mustard, because rodents fed mustard steroids became more muscular. I found another article looking at levels of this steroid in plants and the amounts fed to rodents. The levels in plants was expressed in micrograms per kilogram plant matter, the doses for the animals was given as milligrams per kilogram of rodent.