2. 外语
  3. For years the media, food labels, dietitians, and even scientists who should know better have bombarded (轰炸) us with advice to l

For years the media, food labels, dietitians, and even scientists who should know better have bombarded (轰炸) us with advice to l

admin2013-05-04  57
问题     For years the media, food labels, dietitians, and even scientists who should know better have bombarded (轰炸) us with advice to load up on antioxidants: compounds found mostly in fruits and vegetables that mop up free radicals, which are highly reactive clusters of atoms that have been fingered as the evil-doers responsible for aging and for illnesses from cancer to heart disease.
    Not so fast. First, studies piled up showing that taking antioxidants—even such common and seemingly harmless ones as vitamins C and E—as supplements was not beneficial to health and might even be dangerous. Many of the free radicals that are neutralized by antioxidants perform valuable functions in the body. The most important:fighting toxins (毒素) and fighting cancer. Maybe it’s not such an excellent idea to flood the body with something that neutralizes these warriors of the immune system. Or as British chemist and science writer David Bradley noted in his blog,Reactive Reports,"It’s always struck: me as odd that you would want to absorb extra antioxidants anyway, given that oxidizing agents are at the front-line of immune defense against pathogens (病原体) and cancer cells...Suffice to say that taking antioxidant supplements... may not necessarily be good for your health if you already have health problems, especially cancer or an infection. "
    The first hints that the trend was crashing came from the hundreds of studies that have tried to assess the health effects of antioxidant supplements. The results have not been pretty. In 2008 the Cochrane Collaboration, an international organization of scientists who assess medical research, carefully checked 67 studies with nearly 400,000 participants. The goal;to determine whether antioxidant supplements reduce mortality in either healthy people or in people with diseases. Conclusion:" We found no evidence to support antioxidant supplements for primary or secondary prevention, and Vitamin A and E may increase mortality. " In analyses of antioxidant supplements and Lou Gehrig’s disease, Alzheimer’s or mild cognitive impairment, and lung cancer, the Cochrane scientists’ verdict was the same: no. And each analysis had an alarming refrain about increasing overall mortality.
    It’s not clear why antioxidants in supplement form might be so dangerous. One idea holds that at high doses they become pro-oxidants,stimulating the harmful DNA- and cell-damaging reactions they’re supposed to prevent. But a more likely explanation is that we are seeing the human version of what scientists are finding in studies of lab animals: antioxidants interfere with immune-system cells that fight infection and cancer.
David Bradley’s Reactive Reports indicates it is______.
选项 A、harmful for us to prevent from antioxidant supplements
B、good for us to fight against the oxidizing agents
C、unwise for us to take antioxidant supplements
D、necessary for us to fight against aging and illness
答案C
解析 推理判断题。定位句指出，正如英国化学家、科学作家大卫·布莱德利在博客《反应报告》中提到的那样：“氧化剂是处在免疫系统最前线与病原体和癌细胞抗争的卫士，而你却要摄取更多的抗氧化剂，那你一定是疯了；完全可以这样说，如果你的健康已经出现问题，尤其是患癌症或被感染，服用抗氧化物补充剂很可能不会给你的健康带来好处。”以上例子表明，服用抗氧化物补充剂对人体有害，我们最好不要服用。因此，C)“服用抗氧化物补充剂是不明智的”符合题意，故为本题答案。A)“抑制抗氧化物补充剂对我们是有害的”和B)“与氧化物抗争对我们是有利的”，均与原文意思相反，故排除；D)“与老龄化和疾病抗争是必要的”，与原文无关，故排除。
转载请注明原文地址:https://www.kaotiyun.com/show/LDB7777K
0

大学英语六级

相关试题推荐
随机试题
最新回复(0)