Antioxidants: Synergy Is the Key with Antioxidants
( Advanced Supplements & Nutrition Science ) ..
Can you really get too much of a good thing? Unfortunately, yes even for hard-to-resist things like food, sex and wine. Apparently, the situation is no different for antioxidants. In April of this year, the National Academy of Sciences set standards for daily upper levels for
Vitamin C, Vitamin E and selenium (see 'Antioxidaut Ceilings").'
Upper levels are defined as the most you can get in a day without risking certain side effects: diarrhea for Vitamin C, nausea for Vitamin B (and possibly bleeding for people who also take certain blood-thinning drugs), and hair and nail loss for selenium. Although no upper
levels for carotenoids were given, scientists warn against taking high doses of beta- carotene by itself in pill form. Apparently two out of three studies found that smokers given concentrated heta-carotene pills get more lung can occur than those given a placebo. The opposite
is true for dietary beta-carotene, with those who cat plenty of orange vegetables and cantaloupe getting lung cancer much less often than those who seldom eat these foods.
Trials giving only one antioxidant to humans may fail because annoxidants work as part of a team. Naturally, fruits and vegetables contain many other antioxidants besides beta-carotene - induding alpha-carotene and Vitamin C, to name only two and, hy way of synergy combinations
of antioxidants tMer greater free-radical protection than any one antioxidant can. in one study, a mixture of betacarotene,Vitamin E, glutatbione and Vitamin C was found 10 be more effective than each antioxidant given individually in preventing the growth of experimental
(laboratory-induced) cancer of the mouth in hamsters. in fact, when Vitamin C was applied by itself, it actually increased tumor size. Whereas Vitamin B's antioxidant power is regenerated by Vitamin C, beta-carotene works in synergy with Vitamin B to protect membranes from
free-radical damage) Yet many carotenoids and even Vitamin C can act as prn-oxidants, or free-radical generators.
When given alone and in high doses, again highlighting the importance of a balanced and moderate approach to supplementation. Apart from the hazards of one big dose and the benefits of synergy, you should also consider the hang for your buck when deciding how much to in one
double-blind study 300 mg of Vitamin C bolstered levels of the important antioxidant glutathione by almost 50% in the red blood cells of healthy adults eating a Vitamin C-restricted diet. When the close was raised to 2,000 mg, however, no additional benefit was seen: We can
only conclude from this and other studies like it that a point of diminishing returns exists for antioxidant supplementation beyond which benefits level off With antioxidants, as with life, variety and moderation are rules to live by.
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