VOA慢速英语2013 健康报道 - 叶酸能否预防儿童自闭症？

Health Report - Can Folic Acid Prevent Childhood Autism?

健康报道 - 叶酸能否预防儿童自闭症？

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

这里是美国之音慢速英语健康报道。

A new study found that women who took folic acid supplements in early pregnancy 1 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 disorders 2 in children.

一项新的研究发现，怀孕早期服用叶酸补充剂的妇女生下患有自闭症孩子的几率更小。叶酸是一种B族维生素，能够帮助身体生成和修复细胞。这项研究未能证明叶酸可以预防儿童自闭症，但研究结果表明两者之间存在某种联系。研究人员呼吁调查叶酸是否能够降低儿童患上其它脑部疾病的风险。

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

自闭症儿童在和他人沟通、交往上存在障碍。

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

挪威公共卫生研究所的研究人员查看了2002年到2008年出生的8.5万名儿童的记录。

The study asked mothers to describe their diets, including vitamins and other nutritional 3 treatments, before and during their pregnancies 4. 

这项研究让母亲们回忆了她们怀孕前后的饮食，包括维生素和其它营养治疗。

Research leader Pal 5 Suren and his colleagues compared the women who took folic acid supplements to those who did not.

研究负责人Pal Suren和他的同事对服用和未服用叶酸补充剂的妇女进行了对比。

“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.”

他说，“在怀孕早期服用叶酸补充剂的妇女生下患有自闭症孩子的几率大幅下降了40%。”

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 halfway 6 through pregnancy had no effect.

他表示，服用叶酸以降低自闭症风险的最佳时机似乎是怀孕前四周到怀孕后八周。研究人员发现，在怀孕中期服用叶酸并无效果。

After the babies were born, investigators 7 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 syndrome 8 to make any findings.

婴儿出生后，研究人员继续对这些孩子进行跟踪调查直到2012年3月底，希望找出有多少儿童会患上各种自闭症。结果发现有270名儿童患上了某种自闭症。研究发现某些种类自闭症的患病风险并没有降低。但研究确实发现最严重的一些自闭症的风险降低了。本次研究未发现足够数量的儿童患上被称为艾斯伯格综合症的轻微自闭症，无法就此做出任何结论。

The cause of autism is not known, but several genes 9 may play a part.

自闭症的成因尚不得而知，但一些基因可能起到了作用。

Folic acid has been linked to the development of a protective covering called the neural 10 tube in a fetus 11. Women who do not get enough folic acid are at risk of giving birth to infants with part of their spinal 12 cord or brain exposed. This disabling condition is called spina bifida.

叶酸与胚胎中一种被称为神经管的保护层的形成联系到了一起。服用叶酸不足的妇女存在生下脊髓或脑部部分外露的婴儿的风险，这种畸形被称为脊柱裂。

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

纽约哥伦比亚大学的Ezra Susser是这项关于叶酸的新研究的合著者。

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

“推荐补充叶酸早有其它原因。而这次研究更增加了我们应该推荐服用叶酸的理由。”

Dark leafy vegetables, asparagus, broccoli 13 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, yeast 14 and liver.

绿叶蔬菜、芦笋、花椰菜和柑橘类水果都富含叶酸，这是天然形式的叶酸。豌豆、扁豆、蚕豆、鸡蛋、酵母和肝脏也含有叶酸。

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.

研究表明，许多孕妇在饮食中并未获得预防神经管缺陷所必需的足量叶酸。因此通常建议孕妇服用叶酸补充剂。有的国家在面粉中添加了叶酸，但挪威并未这样做。

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

这项研究发表在《美国医学协会》期刊上。