4. At high doses, antioxidants become pro-oxidant
There is an idea that when used in high doses, antioxidants can become pro-oxidant but research into ascorbic acid contradicts this theory.
At low concentrations ascorbic acid behaves as a pro-oxidant but at high concentrations it becomes an antioxidant, the review said.
“This contradicts the idea that a high concentration of an antioxidant always has a pro-oxidant effect.”
“There seems to be confusion between the high dose relationship to toxicity according to Paracelsus and the notion of pro-oxidant behaviour. Nevertheless, this misconception persists.”