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For years, doctors advised their patients that the only thing taking multivitamins does is give them expensive urine. After all, true vitamin deficiencies are practically unheard of in industrialized countries. Now it seems those doctors may have been wrong. The result of a growing number of studies suggests that even a modest vitamin shortfall can be harmful to your health. Although proof of the benefits of multivitamins is still far from certain, the few dollars you spend on them is probably a good investment.

Or at least that’ s the argument put forward in the New England Journal of Medicine. Ideally, say Dr. Walter Willett and Dr. Meir Stampfer of Harvard, all vitamin supplements would be evaluated in scientifically rigorous clinical trials. But those studies can take a long time and often raise more questions than they answer. At some point, while researchers work on figuring out where the truth lies, it just makes sense to say the potential benefit outweighs the cost.

The best evidence to date concerns foliates, one of the B vitamins. It’ s been proved to limit the number of defects in embryos, and a recent trial found that foliate in combination with vitamin B12 and a form of B6 also decreases the re-blockage of arteries after surgical repair.

The news on vitamin E has been mixed. Healthy folks who take 400 international units daily for at least two yean appear somewhat less likely to develop heart disease. But when doctors give vitamin E to patients who already have heart disease, the vitamin doesn’ t seem to help. It may turn out that vitamin E plays a role in prevention but cannot undo serious damage.

Despite vitamin C’ s great popularity, consuming large amounts of it still has not been positively linked to any great benefit. The body quickly becomes saturated with C and simply excretes any excess.

The multivitamins question boils down to this: Do you need to wait until all the evidence is in before you take them, or are you willing to accept that there’ s enough evidence that they don’ t hurt and could help?

If the latter, there’ s no need to go to extremes and buy the biggest horse pills or the most expensive bottles. Large dose can cause trouble, including excessive bleeding and nervous system problems.

Multivitamins are no substitute for exercise and a balanced diet, of course. As long as you understand that any potential benefit is modest and subject to further refinement, taking a daily multivitamin makes a lot of sense.

单选题 At one time doctors discourages taking multivitamins because they believed that multivitamins _____.
【正确答案】 A
【答案解析】由文章第一段首句“For years, doctors advised their patients that the only thing taking multivitamins does is give them expensive urine. ” 可知多年来， 医生建议他们的病人说， 服用复合维生素唯一的好处就是让他们产生昂 贵的尿液。 言下之意是： 服用复合维生素没有什么好处， 因为它不能被身体吸收。
单选题 According to the author, clinical trials of vitamin supplements _____.
【正确答案】 B
【答案解析】文章第二段第三句提到“But those studies can take a long time and often raise more questions than they answer. ” ， 由此可知维生素补充剂的临床试验研究可能需要很长时间， 而且往往提出的问题比答案要多。 选项B符合原文表达， 答案选B。
单选题 It has been found that vitamin E _____.
【正确答案】 C
【答案解析】文章第四段最后一句提到“It may turn out that vitamin E plays a role in prevention but cannot undo serious damage. ” ， 由此可知维生素E在预防心脏病中起着重要作用， 但却不能完全治愈心脏病。
单选题 It can be seen that large doses of multivitamins _____.
【正确答案】 A
【答案解析】根据文章倒数第二段最后一句“Large doses can cause trouble， including excessive bleeding and nervous system problems. ” 可知服用大剂量的维生素可能会带来问题， 例如大出血和神经系统问题， 所以选项A符合原文意思。
单选题 The author concludes the passage with the advice that _____.
【正确答案】 D
【答案解析】文章最后一段末句提到“As long as you understand that any potential benefit is modest and subject to further refinement, taking a daily multivitamin makes a lot of sense. ” ， 作者认为只要你明白 任何潜在的好处都是有限的， 而且其效果也是逐渐体现出来的， 那么， 每天服用一点复合维生素也是有道理的。