2007年VOA标准英语-Folic Acid Linked to Colon Polyps

By Melinda Smith
Washington, D.C.
07 June 2007
 

For years, doctors urged women to take folic acid if they planned to get pregnant. Then researchers discovered the nutrient¹ helped reduce the risk of a heart attack. But now a new study shows folic acid may stimulate² the growth of polyps in the colon³. And as VOA reports, polyps can lead to colon cancer.

Many companies produce folic acid supplements

Women often take folic acid to prevent birth defects.  Other women, and men, take it to help reduce the level of homocysteine in the blood.  Too much homocysteine can possibly lead to heart attacks.

Gastroenterologists check a patient's colon during a procedure known as a colonoscopy.  A new study published in the Journal of the American Medical Association shows that taking too much folic acid can cause polyps in the colon. 

Doctor John Baron⁴ of Dartmouth University School of Medicine in the United States says the presence of polyps raises the risk of cancer.  "Most colon polyps are benign⁵ and the reason to worry about them is simply that if you can remove them, you can prevent their developing into cancer," he says.

The American study of 1,000 people was equally divided between those who took one milligram of folic acid and those who took a placebo⁶ -- a 'sugar' pill or a pill with no medicine ingredient.

Researchers were trying to determine if folic acid prevented polyps.  Dr. Baron says what researchers found surprised them.  "We found that folic acid did not decrease the risk of colon polyps. In fact, in some analysis we saw suggestions that folic acid might increase risk of those polyps."

Not only did the vitamin stimulate their growth, they also increased the risk of something else affecting men in the group. "We also saw an increase in the risk of prostate cancer in the folate group,” Dr. Baron adds.  “This is a surprising finding.  It's far from definitive⁷, but it's something that should be looked into in the future."

Folic acid is a type of B vitamin.  Combined with vitamins B-12 and C, it helps the body create and use protein.  It also forms red blood cells and produces the genetic⁸ makeup⁹, called DNA¹⁰.

Folic acid is found in many of the foods we eat:  for example, dark green leafy vegetables, wheat grains, beans and other legumes.

So with the exception of women who want to deliver a healthy baby, an extra supplement of folic acid may not be a good thing.  At least until another study comes out.

1 nutrient   

adj.营养的，滋养的；n.营养物，营养品

参考例句：

• Magnesium is the nutrient element in plant growth.镁是植物生长的营养要素。
• The roots transmit moisture and nutrient to the trunk and branches.根将水分和养料输送到干和枝。

2 stimulate   

vt.刺激，使兴奋；激励，使…振奋

参考例句：

• Your encouragement will stimulate me to further efforts.你的鼓励会激发我进一步努力。
• Success will stimulate the people for fresh efforts.成功能鼓舞人们去作新的努力。

3 colon   

n.冒号，结肠，直肠

参考例句：

• Here,too,the colon must be followed by a dash.这里也是一样，应当在冒号后加破折号。
• The colon is the locus of a large concentration of bacteria.结肠是大浓度的细菌所在地。

4 baron   

n.男爵；(商业界等)巨头，大王

参考例句：

• Henry Ford was an automobile baron.亨利·福特是一位汽车业巨头。
• The baron lived in a strong castle.男爵住在一座坚固的城堡中。

5 benign   

adj.善良的，慈祥的；良性的，无危险的

参考例句：

• The benign weather brought North America a bumper crop.温和的气候给北美带来大丰收。
• Martha is a benign old lady.玛莎是个仁慈的老妇人。

6 placebo   

n.安慰剂；宽慰话

参考例句：

• The placebo has been found to work with a lot of different cases.人们已发现安慰剂能在很多不同的病例中发挥作用。
• The placebo effect refers to all the observable behaviors caused by placebo.安慰剂效应是指由安慰剂所引起的可观察的行为。

7 definitive   

adj.确切的，权威性的；最后的，决定性的

参考例句：

• This book is the definitive guide to world cuisine.这本书是世界美食的权威指南。
• No one has come up with a definitive answer as to why this should be so.至于为什么该这样，还没有人给出明确的答复。

8 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

9 makeup   

n.组织；性格；化装品

参考例句：

• Those who failed the exam take a makeup exam.这次考试不及格的人必须参加补考。
• Do you think her beauty could makeup for her stupidity?你认为她的美丽能弥补她的愚蠢吗？

10 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。