2009年12月英语六级阅读理解的全真模拟题五_大学英语阅读

2009年12月英语六级阅读理解的全真模拟题五

　　The best evidence to date concerns folate, one of the B vitamins. Its been proved to limit the number of defects in embryos , and a recent trial found that folate in combination with vitamin B 12 and a form of B6 also decreases the re-blockage of arteries after surgical repair.

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

　　Despite vitamin Cs 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 theres enough evidence that they dont hurt and could help?

　　If the latter, theres no need to go to extremes and buy the biggest horse pills or the most expensive bottles. Large doses 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.