A new technique developed by researchers from the University of Granada for antioxidants in food have shown that orange juice is ten times more beneficial than believed so far.
The study highlights the need to rewrite the tables on the antioxidant capacities of food products.
Orange, mandarin, lemon and grapefruit juices of citrus fruits have emerged many times more beneficial under the new lab technique. For example, in the case of orange juice, the value jumps from traditional 2.3 mmol Trolox/L (units for the antioxidant capacity) to 23 mmol Trolox/L with the new GAR method.
"The antioxidant activity is, on average, ten times higher than that which everyone thought up until now, and not just in juices, but also in any other kind of food analysed with this methodology," José Ángel Rufián Henares, professor at the University of Granada told Sinc.
Traditional methods to calculate antioxidants have used a simulation that analysed only the liquid fraction of what we eat.
It calculated the antioxidant capacities of only those substances that can potentially be absorbed in the small intestine.
But the current work shows that there is an antioxidant activity of the solid fraction (the fibre) which isn't measured.
The large intestinal microbiota are able to extract more antioxidants from this insoluble fraction and this can be measured by the new methodology.
The technique called 'global antioxidant response' (GAR) includes an in vitro simulation of the gastrointestinal digestion that occurs in our body, whilst taking into account the 'forgotten' antioxidant capacity of the solid fraction.
The work has been published in the journal Food Chemistry.
Antioxidants are man-made or natural substances that may prevent or delay some types of cell damage. Antioxidants are found in many foods, including fruits and vegetables.
The three major antioxidant vitamins are beta-carotene, vitamin C, and vitamin E. You'll find them in colourful fruits and vegetables, especially those with purple, blue, red, orange, and yellow hues.
Antioxidants have been increasingly added to flavoured water and other products to earn a "high in antioxidants" label but studies have cautioned against getting carried away. They may not be the fix for everything.
Finally, moderation is the best way out.