首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Many nutritionists, having known for decades that saturated fat, found in abundance in red meat and dairy products, raise
Many nutritionists, having known for decades that saturated fat, found in abundance in red meat and dairy products, raise
admin
2011-01-17
42
问题
Many nutritionists, having known for decades that saturated fat, found in
abundance in red meat and dairy products, raises blood cholesterol levels that
are in turn associated with a high risk of coronary heart disease, have fallen
Line victim to the temptation of simplifying dietary recommendations to facilitate
(5) public nutrition education. After decades of promoting the consumption of all
complex carbohydrates and eschewing all fats and oils, much of this theory has
been discredited.
Controlled feeding studies in which the participants eat carefully prescribed
diets for several weeks substantiated that saturated fat increases cholesterol
(10) levels, and that polyunsaturated fat-found in vegetable oils and fish-reduces
cholesterol. Dietary advice should therefore emphasize the replacement of
saturated fat with polyunsaturated fat, not total fat reduction. The subsequent
doubling of polyunsaturated fat consumption that this advice might inspire could
potentially contribute to a halving of coronary heart disease rates.
(15) Indeed, the argument that fat in general is to be avoided has been hastily
extrapolated from observations that affluent Western countries have both high intakes
of fat and high rates of coronary heart disease. This correlation is limited to saturated
fat, however, for societies in which people eat relatively large portions of
monounsaturated and polyunsaturated fat (whose health benefits are nearly identical)
(20) tend to have lower rates of heart disease. On the Greek island of Crete, for
instance, where the traditional diet contained much olive oil, a rich source of
monounsaturated fat, and fish, a source of polyunsaturated fat, fat constituted
40 percent of the calories in this diet, but the rate of heart disease was lower
than the rate for those who followed the traditional diets of Japan, where fat
(25) composes only 8 to 10 percent of the calories. Furthermore, international
comparisons of overall fat intake can be misleading: many negative influences
on health, such as smoking, physical inactivity and high amounts of body fat,
are also correlated with Western affluence. Many nutritionists decided it would
be too difficult to educate the public about these subtleties, instead advocating a
(30) clear, simple message that fat was insalubrious.
The wisdom of this practice has further come into question as researchers
discover that the two main cholesterol-carrying chemicals, low-density
lipoprotein (LDL), and high-density lipoprotein (HDL), have very different
effects on the risk of coronary heart disease, such that increasing the ratio of
(35) LDL to HDL in the blood raises the risk, whereas decreasing the ratio has the
opposite effect. Unfortunately, certain controlled feeding studies have shown
that when a person replaces calories from saturated fat with an equal amount of
calories from carbohydrate-rich polyunsaturated fats, not only the levels of LDL
and total cholesterol diminish, but also the level of HDL, and thus in only a
(40) limited reduction in risk accrues from shifting to a polyunsaturated fat diet.
According to the passage, which of the following is characteristic of lipoproteins?
选项
A、The dangers of lower density lipoproteins and the dangers of higher density lipoproteins are remarkably similar in the case of coronary heart disease.
B、A higher ratio of higher density lipoproteins to lower density lipoproteins has a salubrious effect on heart disease.
C、A shift from a polyunsaturated fat diet to a saturated fat diet tends to increase the risk of coronary heart disease stemming from high-density lipoproteins.
D、A shift from a polyunsaturated fat diet to a saturated fat diet tends to decrease the risk of coronary heart disease stemming from low-density lipoproteins.
E、Controlled feeding studies have yet to establish the feasibility of attempting to manipulate lipoprotein ratios through dietary change.
答案
B
解析
转载请注明原文地址:https://jikaoti.com/ti/iJWYFFFM
本试题收录于:
GRE VERBAL题库GRE分类
0
GRE VERBAL
GRE
相关试题推荐
In2014,olderAmericansfell29milliontimes,leadingto7millioninjuries,accordingtoareportpublishedlastweek.About
Dr.JamesBarrywasthefirstwomaninEnglandtogotomedicalschool.Whenshewasgrowingup,womencouldnotgotomedicals
TheCalifornialawmakersvotedThursdaytoraisethelegalagetobuytobaccoproductsfrom18to21.Themeasureispartofal
TheCalifornialawmakersvotedThursdaytoraisethelegalagetobuytobaccoproductsfrom18to21.Themeasureispartofal
Understandingthistransitionrequiresalookatthetwo-sidedconnectionbetweenenergyandhumanwell-being.Energycontribute
SpeakerA:DoyouknowBeijingopera?SpeakerB:Ofcourse.【D5】______SpeakerA:CanyouintroduceBeijingoperatome?I
Whichofthefollowingbeststatesthemainideaofthepassage?Informationinthepassagesupportswhichofthefollowingsta
Inanattempttoimprovetheoverallperformanceofclericalworkers,manycompanieshaveintroducedcomputerizedperformancemo
DOCUMENTS:FORGE::
HistorianF.W.Maitlandobservedthatlegaldocumentsarethebest—indeed,oftentheonly—availableevidenceabouttheeconomic
随机试题
症见水肿反复消长不已,面浮身肿,腰以下甚,按之凹陷不起,尿量减少,腰酸冷痛,四肢厥冷,怯寒神疲,甚者心悸胸闷,喘促难卧,腹大胀满,舌质淡胖,苔白,脉沉细,辨证为
确诊恶性骨肿瘤最可靠的依据是
A.7-羟基黄酮B.七叶内酯C.大黄酸D.苦参碱E.葡萄糖醛酸秦皮中含有香豆素化合物是()。
A.清宁丸B.加味保和丸C.槟榔四消丸D.麻仁滋脾丸E.九制大黄丸患者,女,67岁,大便秘结,面色无华,头晕目眩,口干,舌淡苔少,脉细涩,辩证为津亏肠燥,治宜选用的中成药是()。
关于收入的特征,以下正确的是()。
那些植物看起来好长时间没有浇水了。
晓敏几乎每晚都将所有的时间用来复习当天学习的新知识,但是复习效果不佳,每次复习过的知识没多久就会忘记。同学们知道小敏的困惑后,都很热心地向小敏分享复习的建议。以下建议中,说法不正确的是()
试利用变量代换x=cost将微分方程化为关于y,t的方程,并求原方程的通解.
若f’(x)=sinx,则f(x)的原函数之一是
Whatistherelationshipbetweenthewords"color"and"red"?
最新回复
(
0
)