The Food Journal and Food, Nutrition & Science

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Too Many Anti-Oxidants?

Too Many Anti-Oxidants?

Shoppers and Trends

September 28, 2008

Dear Phil,
In addition to the large number of foods that contain anti-oxidants naturally, there are an increasing number of products out there containing added anti-oxidants. Can you over-consume them?
Antioxidants are a group of vitamins like carotenoids, vitamins A, C, and E, and the mineral selenium. They are believed to neutralize free radicals – the unstable molecules that lead to oxidative, cancer-causing damage in the body.
Based on some recent National Cancer Institute studies, however, certain anti-oxidants, like beta-carotene, can become pro-oxidants (generating free radicals) under special circumstances (at high doses, under high oxygen concentrations, etc.).
In fact, a recent trial that investigated the separate effects of beta-carotene, vitamins C and E, and beta-carotene plus vitamins C and E on colorectal adenomas found that among non-smokers and non-drinkers, the anti-oxidants provided protection. But there was an increase in carcinogenic effects among smokers and drinkers.
Melanin is another anti-oxidant that appears to have both anti-oxidant and pro-oxidant capabilities, depending on the situation. Research also shows that the timing of an anti-oxidant’s administration may have an effect on how useful it is in fighting off cancer. How it’s administered (what it’s combined with, etc.) does too.
Keep in mind that supplements are not substitutes for the foods that contain anti-oxidants, as overall diet and lifestyle choices are more crucial in preventing diseases than your intake of any one nutrient. Include antioxidant rich foods (like fruits, vegetables, whole grains and legumes) as part of your daily diet.
Ultimately, there is not enough research out there for physicians to recommend specific courses of treatment using anti-oxidants, though there is a significant amount of marketing out there pushing anti-oxidant supplementation.
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