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Passage 1 IF VITAMIN C is good for you, does more mean better? Millions of people think so but scientists have been divided on the issue. Despite a huge research effort, there is little evidence that megadoses of vitamin C, up to 100 times the recommended daily amounts, have beneficial effects. Now an American scientist has come up with an explanation of the lack of effect—and a simple remedy. Millions of Americans take supplements of the vitamin in the belief that its anti-oxidant properties help prevent heart disease, cancer and the ageing process. Most of it, however, goes straight down the pan: the body cannot deal with excess vitamin C, which is rapidly excreted. Even large doses are eliminated in 12 hours and slow-release ones in 16. The way to keep blood levels of the vitamin continuously high, according to Roc Ordman, Professor of Biochemistry at Beloit College, Wisconsin, is to take it twice a day—one 500 milligram does every 12 hours. “If vitamin C really does work as an antioxidant, then taking a supplement once a day might be like wearing a condom half the time.” Professor Ordman said. “Nobody has ever thought to look at how much you have to take to keep the level elevated.” In a study published in the current issue of the gerontology journal Age, Professor Ordman gave varying doses of vitamin C at different times to students and measured the amount excreted in their urine. He found a 500 mg dose was needed every 12 hours “to enrich the blood just enough to ensure there is a little bit leaking out all the time.” This compares with the US-recommended adult daily allowance of 60 mgs. Recommended levels of vitamin C, and other vitamins, have been raised following recognition of their role in mopping up “free radicals” in the blood linked with a range of diseases. However, the British figure of 40 mgs daily for vitamin C is still below the U.S. figure and likely to be raised again. Research on megadoses of vitamin C of 10 and 20 times this level have shown it to have some protective effect against the common cold taken at the first sign. But there is no evidence of a beneficial effect against other diseases of doses vastly higher than the recommended daily amounts. LINUS PAULING, the Nobel Laureate, whose book on vitamin C and the common cold in 1970 popularised the idea of taking fistfuls of supplements, is said to have swallowed 10,000 mgs a day. It is because it is water-soluble and quickly excreted that vitamin C is safe in such quantities; it does not build up in the tissues. Professor Ordman’s twice-daily regime may help keep blood levels of the vitamin high. But dosing on the scale followed by Pauling, who died last August aged 93, will seriously damage your bank balance—at $ 2,500 a year. 1. What do you know about Professor Ordman’s view towards vitamin C from the passage? 2. Why was the Nobel Prize winner Linus Pauling mentioned in the passage? 3. Explain in your town words the sentence from paragraph 2 “Most of it, however, goes straight down the pan”. 4. What is concluded about effects of megadoses of vitamin C in the passage?
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