2. 考研
  3. Calories and Human Health Dieting, according to an old joke, may not actually make you live longer, but it sure feels that w

Calories and Human Health Dieting, according to an old joke, may not actually make you live longer, but it sure feels that w

admin2013-07-08  60
问题                     Calories and Human Health
    Dieting, according to an old joke, may not actually make you live longer, but it sure feels that way. Nevertheless, evidence has been accumulating since the 1930s that calorie restriction—reducing an animal’s energy intake below its energy expenditure—extends lifespan and delays the onset of age-related diseases in rats, dogs, fish and monkeys. Such results have inspired thousands of people to put up with constant hunger in the hope of living longer, healthier lives. They have also led to a search for drugs that mimic the effects of calorie restriction without the pain of going on an actual diet.
    Amid the hype(intensive publicity), it is easy to forget that no one has until now shown that calorie restriction works in humans. That omission, however, changed this month, with the publication of the initial results of the first systematic investigation into the matter.
    This study, known as CALERIE (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy), was sponsored by America’s National Institutes of Health. It took 48 men and women aged between 25 and 50 and assigned them randomly to either a control group or a calorie-restriction regime. Those in the second group were required to cut their calorie intake for six months to 75% of that needed to maintain their weight.
    The CALERIE study is a landmark in the history of the field, because its subjects were either of normal weight or only slightly overweight. Previous projects have used individuals who were clinically obese, thus confusing the unquestionable benefits to health of reducing obesity with the possible advantages of calorie restriction to the otherwise healthy.
    At a molecular level, CALERIE suggests these advantages are real. For example, those on restricted diets had lower insulin resistance and lower levels of low-density lipoprotein cholesterol. They showed drops in body temperature and blood-insulin levels—both phenomena that have been seen in long-lived, calorie-restricted animals. They also suffered less oxidative damage to their DNA.
    Eric Ravussin, of Louisiana State University in Baton Rouge, who is one of the study’s authors, says that such results provide support for the theory that calorie restriction produces a metabolic adaptation over and above that which would be expected from weight loss alone. Nevertheless, such metabolic adaptation could be the reason why calorie restriction is associated with longer lifespans in other animals—and that is certainly the hope of those who, for the past 15 years, have been searching for ways of triggering that metabolic adaptation by means other than semi-starvation.
It can be inferred from the last paragraph that______.
选项 A、the metabolic adaptation solely resulted from weight loss
B、the metabolic adaptation is what dieters are pursuing
C、semi-starvation was seen as an effective means for weight loss
D、people had no idea about the metabolic adaptation before CALERIE
答案B
解析 判断推理题。考查是非细节。文章最后一段提到一些人寻找能够引发新陈代谢调节能力的新方法，以期结束半饥饿的状态；可见人们最终追求的是新陈代谢调节能力，因此选[B]。[A]项中solely错误，减轻体重并不是引发新陈代谢调节功能的唯一原因，如果是这样人们就不必费尽心思寻找；[C]项半饥饿状态只是人们不得以的选择，正因为此人们才不断寻找新的替代方法；[D]项人们在CALERlE之前已经知道了新陈代谢能力调节，不明白的是其中的科学依据。
转载请注明原文地址:https://kaotiyun.com/show/tsO4777K
0

考研英语一

相关试题推荐
随机试题
最新回复(0)