• 所属考试大学英语四级试题库
  • 试题题型【阅读理解 Section B】
Definitions of ObesityA. How does one define when a person is considered to be obese and not just somewhat overweight? Height-weight tables give an approximate guideline as to whether one is simply overweight or has passed into the obese stage.
B. The World Health Organization recommends using a formula that takes into account a person's height and weight.-The"Body Mass Index" (BMI) is calculated by dividing the person's weightin kilograms by the square of their height in meters, and is thus given inunits of kg/m2. A BMI of 18.5-24.9 is considered to be the healthiest. A BMI of between 25 and 29.9 is considered to be overweight, while a BMI of over 30 is considered to be obese.
C. However, it is recognized that this definition is limited as it does not take into account such variables as age,gender and ethnic origin, the latter being important as different ethnic group shave very different fat distributions. Another shortcoming is that it is not applicable to certain very muscular people such as athletes and bodybuilders,who can also have artificially high BMIs. Agencies such as the National Cholesterol Education Program (NCEP) in the USA and the International Diabetes Foundation (IDF) are starting to define obesity in adults simply in terms of waist circumference. 
Health Effects of Obesity
D. Over 2000 years ago, the Greek physician Hippocrates wrote that" persons who are naturally very fat are apt to die earlier than those who are slender". This observation remains very true today.Obesity has a major impact on a person's physical, social and emotional well-being. It increases the risk of developing diabetes mellitus type 2("mature onset diabetes") and also makes Type 2 diabetes more difficult to control. Thus weight loss improves the levels of blood glucose and blood fats, and reduces blood pressure. The association between obesity and coronary heart disease is also well-known. 
E. Furthermore, in 2001 medical researchers established a link between being overweight and certain forms of cancer, and estimated that nearly 10,000 Britons per year develop cancer as a result ofbeing overweight. This figure was made up of 5,893 women and 3,220 men, with the strongest associations being with breast and colon cancers. However, it is thought that being overweight may also increase the risk of cancer in there productive organs for women and in the prostate gland for men.
F. The link between breast cancer and nutritional status is thought to be due to the steroid hormones, oestrogen and progesterone, which are produced by the ovaries, and govern a woman's menstrual cycle. Researchers have found that the more a woman eats, or the more sedentary her lifestyle, the higher are the concentrations of progesterone. This link could explain why women from less affluent countries have lower rates of breast cancer. Women from less affluent nations tend to eat less food and to lead life styles which involve more daily movement. This lowers their progesterone level, resulting in lower predisposition to breast cancer.
G. The Times newspaper, in 2002 reported that obesity was the main avoidable cause of cancer among non-smokers in theWestern world! 
H. Research published by St Thomas'Hospital, London, UK in 2005 showed a correlation between body fat and aging,to the extent that being obese added 8.8 years to a woman's biological age. The effect was exacerbated by smoking, and a non-overweight woman who smokes 20 cigarettes a day for 20 years added 7.4 years to their biological age. The combination of being obese and a smoker added at least ten years to a woman's biological age, and although the study only involved women, the lead researcher Professor Tim Spector believes the finding would also apply to men.
I. The aging effect was determined by measuring the length of telomeres, tiny "caps" on the ends of chromosomes,which help protect the DNA from the ageing process. Indeed, telomeres have been dubbed the "chromosomal clock" because, as an organism ages, they become progressively shorter, and can be used to determine the age of the organism. Beyond a certain point, the telomere becomes so short that it is nolonger able to prevent the DNA of the chromosome from falling apart. It is believed that excess body fat and the chemicals present in tobacco smoke release free radicals which trigger inflammation. Inflammation causes the production of white blood cells which increases the rate of erosion oftelomeres.
J. Recent research (2005) conducted in the USA shows that obesity in middle age is linked to an increased risk of dementia, with obese people in their 40s being 74% more likely to develop dementia compared to those of normal weight. For those who are merely overweight, the lifetime risk of dementia risk was 35% higher.
K. Scientists from the Aging Research Centre at the Karolinska Institute in Sweden have been able to take information such as age, number of years in education, gender, body mass index, blood pressure level, physical activity and genetic factors, assigning each a risk score. They then used this information to devise a predictive test for dementia. This test will enable people at risk, for the first time, to be able to affect life style changes which will reduce their risk of contracting dementia.
Other Problems
L. The world-wide upsurge in obesity,particularly in children, is of major economic concern, liable to drain economies. Of further concern is that research conducted in Australia and published in 2006, shows that up to one third of breech pregnancies were undetected by the traditional "palpation" examination, the danger being greatest for those women who are overweight or obese—a growing proportion of mothers. This means that such women are not getting the treatment required to turn the baby around in time for the birth, and in many cases require an emergency caesarean section.
M. This is a true health-care crisis, far bigger than Severe Acute Respiratory Syndrome (SARS) and ultimately, even bigger than AIDS.
1.[选词填空]The excess body fat, like the chemicals present in tobacco smoke, can lead to inflammation.
    • 解题思路:身体内多余的脂肪,就像烟草里的化学物质,可能会导致炎症。题干关键词excess body fat,tobacco smoke和inflammation。文中I段提到,有人认为,体内多余的脂肪和烟草里的化学物质一样,会释放自由基,进而引起炎症。与题干意思吻合,故选I。
    2.[选词填空]A non-overweight woman who smokes 20 cigarettes a day for 20 years added 7.4 years to her biological age.
      • 解题思路:一个不超重的女人,如果20年内每天吸20支烟,生理年龄会增加7.4岁。题干关键词non-over weight woman,20 cigarettes a day和7.4years。文中H段第二句提到.这种影响会因为吸烟而更加严重,一个不超重的女人,如果20年内每天吸20支烟,生理年龄会增加7.4岁。与题干原文一致,故选H。
      3.[选词填空]Women from less affluent nations tend to have much less breast cancer.
        • 解题思路:来自不太富裕国家的女性遭受乳腺癌的概率要低。题干关键词less affluent nations和less breast cancer。文中F段倒数第三句提到,这种联系可以解释为什么来自不太富裕国家的女性乳腺癌的患病率低。与题干意思吻合,故选F。
        4.[选词填空]Obesity would affect a person's emotional well-being.
          • 解题思路:信息明示题。题干:肥胖会影响一个人的心理健康。题干关键词emotional well—being。文中D段第三句提到,肥胖对人的身体、社会和心理健康有重要影响。与题干意思吻合,故选D。
          5.[选词填空]Obese people in middle age run an increased risk of dementia.
            • 解题思路:中年肥胖人群患痴呆症的风险增加。题干关键词middle age和increased risk of dementia。文中J段第一句提到,最近(2005)美国的一项研究发现,中年肥胖和痴呆风险的增加之间有联系。与题干意思吻合。故选J。
            6.[选词填空]The world-wide upsurge in obesity,especially in children, will possibly drain economies.
              • 解题思路:世界范围内的肥胖率高涨,尤其是儿童的肥胖问题,这很可能会阻碍经济发展。题干关键词world-wide upsurge in obesity,children和possibly draineconomies。文中L段第一句提到.世界范围内的肥胖,尤其是儿童的肥胖问题,是涉及经济的问题,它有可能会阻碍经济发展。与题干意思吻合,故选L。
              7.[选词填空]Obesity has something to do with cancer in the prostate gland for man.
                • 解题思路:对男人来说,肥胖和前列腺癌症有关。题干关键词cancer in the prostate gland。文中E段最后一句提到,据推测,超重会增加女性生殖器官和男性前列腺患癌症的风险。与题干意思吻合,故选E。
                8.[选词填空]"Body Mass Index" is limited in defining a person' s weight ideal, because it does not takes into account Manyvariables such as age, gender and ethnic origin.
                  • 解题思路:使用“身体质量指数”来定义一个人的理想体重是有限的.因为它没有把年龄、性别和种族本源等很多类似的因素考虑在内。题干关键词“Body Mass Index”和age,gender and ethnic origin。文中C段第一句提到,身体质量指数的定义是有限的,它没有包括诸如年龄、性别和种族等变量。与题干意思吻合,故选C。
                  9.[选词填空]Whether one is simply overweight or has passed into the obese stage can be judged according to the height-weight table.
                    • 解题思路:根据身高一体重表可以判断一个人只是超重,还是已经进入肥胖阶段。题干关键词simply overweight,passed into the obese stage和height—weight table。文中A段第二句提到.一个人到底只是超重还是进入了肥胖阶段,身高一体重表可以给出一个大约的参考。与题干意思吻合,故选A。
                    10.[选词填空]The predictive test will help people to change lifestyle, which will reduce their risk of contracting dementia.
                      • 解题思路:痴呆症预测实验可以使一些人改变生活方式,进而减少患痴呆症的风险。题干关键词predictive test,change lifestyle和contracting dementia。文中K段最后两句提到,专家们用这些信息设计预测痴呆的测验。这个测验使得身处危险的人,可以第一时间改变他们的生活方式,进而降低患痴呆症的风险。与题干意思吻合,故选K
                      • 参考答案:I,H,F,D,J,L,E,C,A,K