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
Vitamins To supplement or not? Mineral, vitamin, and anti-oxidant health supplements make up a multi-billion dollar industry
Vitamins To supplement or not? Mineral, vitamin, and anti-oxidant health supplements make up a multi-billion dollar industry
admin
2012-01-16
29
问题
Vitamins To supplement or not?
Mineral, vitamin, and anti-oxidant health supplements make up a multi-billion dollar industry in the united states alone, but do they really work? Evidence suggests supplementation is clearly indicated in special circumstances, but can actually be harmful in others. For the general population, however, supplements have negligible or no impact on the prevention of common cancers, cardiovascular diseases, cognitive decline, mortality or any other major indicators of health. In the pursuit of a longer, happier and healthier life, there are certainly better investments for most people than a tube of vitamin supplements.
Particular sub-groups of the population can gain a proven benefit from supplementation. Folic acid has long been indicated as a prenatal supplement due to its assistance in fetal cell division and corresponding ability to prevent neural-tube birth defects. Since Canada and the United States decided to require white flour to be fortified with folic acid, spinal birth defects have plummeted by 75%, and rates of neuroblastoma (a ravaging form of infant cancer) are now 50% lower. In countries without such fortification, or for women on low-carbohydrate diets, a prenatal multivitamin could make the crucial difference. The United States Department of Health and Human services has concluded that the elderly may also benefit from extra vitamin D; calcium can help prevent bone fractures; and zinc and anti-oxidants can maintain vision while deflecting macular degeneration in people who would otherwise be likely to develop this affliction.
There is mounting evidence, however, for many people to steer clear of multivitamins. The National Institutes of Health has noted a "disturbing evidence of risk" in tobacco users; beta-carotene, a common ingredient in multivitamins, was found over a six-year study to significantly contribute to higher lung cancer and mortality rates in smokers. Meanwhile, excessive vitamin A (a supplement often taken to boost the immune system) has been proven to increase women’s risk of a hip fracture, and vitamin E, thought to improve cardiovascular health, was contraindicated in a study that demonstrated higher rates of congestive heart failure among such vitamin users. Antioxidant supplementation has no purpose nor does it achieve anything, according to the Food and Nutrition Board of the National Academy of Sciences, and the Medical Letter Group has gone further in suggesting they may interfere with treatment and promote some cancers. Antioxidants are generally regarded as counteracting the destructive effect of free radicals in the body, but according to the Medical Letter’s theory, free radicals may also serve the purpose of sending a powerful signal to the body’s immune system to fix the damage. By taking supplements, we risk undermining that message and upsetting the balance of antioxidants and free radicals in the body. The supplements counteract the free radicals, the immune system is not placed on alert, and the disease could sneak through the gates.
One problem with supplementation by tablet is the poor record on digestibility. These tablets are often stocked with metal-based minerals that are essentially miniature rocks, and our bodies are unable digest them. Even the vitamin elements of these pills that are theoretically digestible are often unable to be effectively extracted by our bodies when they arrive in such a condensed form. In salt lake city, for example, over 150 gallons of vitamin and mineral pills are retrieved from the sewer filters each month. According to the physician’s desk reference, only about 10%-20% of multivitamins are absorbed by the body. The National Advisory Board is even more damning, suggesting that every 100 mg of tablet corresponds to about 8.3 mg of blood concentration, although noting that this can still potentially perform a helpful role in some cases. In effect, for every $100 you spend on vitamin supplements, over $90 of that is quite literally flushed down the toilet.
A final argument against multivitamins is the notion that they can lead people—consciously or not—to the conclusion that supplementation fills in the gaps of an unhealthy diet and mops up afterwards, leaving their bodies none the wiser that instead of preparing a breakfast of fresh fruit and muesli, they popped a tiny capsule with coffee and a chocolate bar. In a seven year study, however, the Heart Protection study did not find any positive outcome whatsoever from multivitamins and concluded that while vitamins in the diet are important, multivitamin tablets are safe but completely useless. There is evidently no shortcut around the task of buying, preparing and consuming fresh fruit and vegetables every day. Boosting, supplementing and fortifying products alter people’s very perception of what healthy food is; instead of heading for the fresh produce aisle in the supermarket, they are likely to seek out sugary, processed foods with a handful of extra B vitamins as a healthy choice. We cannot supplement our way out of a bad diet.
Questions 14-16
Choose the correct letter, A, B, C or D.
Write the correct letter in boxes 14-16 on your answer sheet.
Some multivitamin tablets have indigestible ingredients.
选项
A、YES
B、NO
C、NOT GIVEN
答案
A
解析
转载请注明原文地址:https://kaotiyun.com/show/UsNO777K
本试题收录于:
雅思阅读题库雅思(IELTS)分类
0
雅思阅读
雅思(IELTS)
相关试题推荐
Ifppencilscostccents,howmanycanbeboughtforddollars?
In1980,thecostofppoundsofpotatoeswasddollars.In1990,thecostof2ppoundsofpotatoeswasd/2dollars.Bywhatperc
BobandJackshareanapartment.IfeachmonthBobpaysadollarsandJackpaysbdollars,whatpercentofthetotalcostdoesB
Inthefigureabove,m//n.Whichoftheanglesaresupplementaryto∠1?
Mandyhasagardenthatisshapedlikearighttriangle,asshownbelow.Todeterminehowmuchfencingtobuytoenclosehero
Inaboxof10electricalparts,2aredefective.(a)Ifyouchooseonepartatrandomfromthebox,whatistheprobabilitythat
Anantiquesdealerboughtcantiquechairsforatotalofxdollars.Thedealersoldeachchairforydollars.(a)Writeanalgeb
Thetotalcostof8bagelsatabakeryisxdollars.Atthiscostperbagel,whichofthefollowingrepresentsthetotalcost,i
Inaboxof10electricalparts,2aredefective.(a)Ifyouchooseonepartatrandomfromthebox,whatistheprobabilitythat
随机试题
A、腺病毒肺炎B、金黄色葡萄球菌肺炎C、急性感染性喉炎D、支气管哮喘E、肺炎球菌肺炎病情重,稽留热多见
"豹纹刺"属于:
A.乳头血性溢液B.乳头脱屑C.乳头脓性溢液D.乳头白色溢液E.乳头淡黄色溢液
不属于I型变态反应的是
溃疡窦道
引起牙周脓肿最常见的病原菌是
在我国,期货交易所应当以适当方式发布()等信息。[2009年11月真题]
下列有关PPS抽样的说法中,不恰当的有()。
汽车发动机在燃烧时会产生苯,而苯是一种致癌物质。为了应对人类面临的这一威胁,环境保护主义者建议用甲醇来替代汽油,其理由是:燃烧单位数量的甲醇所产生的苯,只是汽油的十分之一。以下哪项如果为真,能构成对上述环境保护主义者建议的质疑?Ⅰ.燃烧甲醇时会产
A-----Guardagainstdamp.J-----Openhere.B-----Handlewithcare.K-----Openindarkroom.C-----Keepaway
最新回复
(
0
)