VOA慢速英语2013 Can Folic Acid Prevent Childhood Autism?

 

Can Folic Acid Prevent Childhood Autism?

From VOA Learning English, this is the Health Report in Special English.

A new study found that women who took folic acid supplements in early pregnancy¹ were less likely to have a child with autism. Folic acid is a B vitamin that helps the body build and repair cells. The study did not prove that folic acid can prevent childhood autism, but the findings suggest a connection. The researchers called for examining whether folic acid is associated with a reduced risk of other brain disorders² in children.

Children with autism have problems communicating and socializing with other people.

Researchers at the Norwegian Institute of Public Health looked at records of more 85,000 children born between 2002 and 2008. 

The study asked mothers to describe their diets, including vitamins and other nutritional³ treatments, before and during their pregnancies⁴. 

Research leader Pal⁵ Suren and his colleagues compared the women who took folic acid supplements to those who did not.

 “The women who took folic acid supplements in early pregnancy had a substantial reduction in risk of having a child with autism. The reduction was 40 percent.”

He says the best time to take folic acid to reduce the risk of autism seems to be from four weeks before to eight weeks after the start of pregnancy. The researchers found that taking folic acid halfway⁶ through pregnancy had no effect.

After the babies were born, investigators⁷ followed up with the children through the end of March 2012. They wanted to find out how many developed any form of autism. Two hundred seventy of the children had some form of autism. The study found no reduction in the risk of some forms of autism. But it did find a lower risk for the most severe form. There were not enough children with a milder form known as Asperger's syndrome⁸ to make any findings.

The cause of autism is not known, but several genes⁹ may play a part.

Folic acid has been linked to the development of a protective covering called the neural¹⁰ tube in a fetus¹¹. Women who do not get enough folic acid are at risk of giving birth to infants with part of their spinal¹² cord or brain exposed. This disabling condition is called spina bifida.

Ezra Susser of Columbia University in New York City was a co-author of the new study of folic acid.

“These supplements are already recommended for other reasons. So this increases the reasons why we should recommend them.”

Dark leafy vegetables, asparagus, broccoli¹³ and citrus fruit are rich sources of folate. Folate is the naturally occurring form of folic acid. Folate is also found in peas, lentils, beans, eggs, yeast¹⁴ and liver.

Studies have shown that many pregnant women get less folate in their diet than they need to prevent neural tube defects. So folic acid supplements are commonly recommended for pregnant women. Some countries add folic acid to flour. Norway does not do that.

The study appears in the Journal of the American Medical Association.

1 pregnancy   

n.怀孕，怀孕期

参考例句：

• Early pregnancy is often accompanied by nausea.怀孕早期常有恶心的现象。
• Smoking during pregnancy increases the risk of miscarriage.怀孕期吸烟会增加流产的危险。

2 disorders   

n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调

参考例句：

• Reports of anorexia and other eating disorders are on the increase. 据报告，厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
• The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》

3 nutritional   

adj.营养的，滋养的

参考例句：

• A diet lacking in nutritional value will not keep a person healthy.缺乏营养价值的饮食不能维持人的健康。
• The labels on food products give a lot of information about their nutritional content.食品上的标签提供很多关于营养成分的信息。

4 pregnancies   

怀孕，妊娠( pregnancy的名词复数 )

参考例句：

• Since the wartime population needed replenishment, pregnancies were a good sign. 最后一桩倒不失为好现象，战时人口正该补充。
• She's had three pregnancies in four years. 她在四年中怀孕叁次。

5 pal   

n.朋友，伙伴，同志；vi.结为友

参考例句：

• He is a pal of mine.他是我的一个朋友。
• Listen,pal,I don't want you talking to my sister any more.听着，小子，我不让你再和我妹妹说话了。

6 halfway   

adj.中途的，不彻底的，部分的；adv.半路地，在中途，在半途

参考例句：

• We had got only halfway when it began to get dark.走到半路，天就黑了。
• In study the worst danger is give up halfway.在学习上，最忌讳的是有始无终。

7 investigators   

n.调查者，审查者( investigator的名词复数 )

参考例句：

• This memo could be the smoking gun that investigators have been looking for. 这份备忘录可能是调查人员一直在寻找的证据。
• The team consisted of six investigators and two secretaries. 这个团队由六个调查人员和两个秘书组成。 来自《简明英汉词典》

8 syndrome   

n.综合病症；并存特性

参考例句：

• The Institute says that an unidentified virus is to blame for the syndrome. 该研究所表示,引起这种综合症的是一种尚未确认的病毒。
• Results indicated that 11 fetuses had Down syndrome. 结果表明有11个胎儿患有唐氏综合征。

9 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪

10 neural   

adj.神经的，神经系统的

参考例句：

• The neural network can preferably solve the non- linear problem.利用神经网络建模可以较好地解决非线性问题。
• The information transmission in neural system depends on neurotransmitters.信息传递的神经途径有赖于神经递质。

11 fetus   

n.胎，胎儿

参考例句：

• In the fetus,blood cells are formed in different sites at different ages.胎儿的血细胞在不同时期生成在不同的部位。
• No one knows why a fetus is not automatically rejected by the mother's immune system. 没有人知道为什么母亲的免疫系统不会自动排斥胎儿。

12 spinal   

adj.针的，尖刺的，尖刺状突起的；adj.脊骨的，脊髓的

参考例句：

• After three days in Japan,the spinal column becomes extraordinarily flexible.在日本三天，就已经使脊椎骨变得富有弹性了。
• Your spinal column is made up of 24 movable vertebrae.你的脊柱由24个活动的脊椎骨构成。

13 broccoli   

n.绿菜花，花椰菜

参考例句：

• She grew all the broccoli plants from seed.这些花椰菜都是她用种子培育出来的。
• They think broccoli is only green and cauliflower is only white.他们认为西兰花只有绿色的，而菜花都是白色的。

14 yeast   

n.酵母；酵母片；泡沫；v.发酵；起泡沫

参考例句：

• Yeast can be used in making beer and bread.酵母可用于酿啤酒和发面包。
• The yeast began to work.酵母开始发酵。