Food sources
Regulatory guidance
In the following discussion, the term "antioxidant" refers mainly to non-nutrient compounds in foods, such as polyphenols, which have
antioxidant capacity in vitro and so provide an artificial index of antioxidant strength – the ORAC measurement. Other than for dietary antioxidant vitamins –
vitamin A,
vitamin C and
vitamin E – no food compounds have been proved with antioxidant efficacy
in vivo. Accordingly, regulatory agencies like the
Food and Drug Administration of the United States and the
European Food Safety Authority (EFSA) have published guidance disallowing food product labels to claim an inferred antioxidant benefit when no such physiological evidence exists.