VOA慢速英语--巧克力爱好者的坏消息：黑巧克力不能提高视力

Bad News for Chocolate Lovers¹: It May Not Help Your Eyesight

Researchers have sad news for chocolate lovers. They found that eating dark chocolate does not improve people’s eyesight as had been thought.

An earlier report suggested that some aspects of eyesight improved within one or two hours of eating chocolate. The new study found no changes in vision² or blood flow after volunteers ate about 20 grams of dark chocolate. Both studies, however, involved only a small number of test subjects.

With two similar-sized tests producing opposite results, “more research is needed,” said the organizers of the latest study. The lead researcher was Jacob Siedlecki of Ludwig-Maximilians-University in Munich, Germany.

Additional³ testing with larger sample sizes would be needed to rule in or out possible long-term benefits,” the researchers wrote. Their report appears in the medical publication⁴ JAMA Ophthalmology.

The reason for suspecting dark chocolate might help with vision is that the sweet treat has plenty of flavonoids, which are antioxidants.

Antioxidants are man-made or natural substances that may prevent or delay some forms of cell damage. Studies have shown that foods with high levels of antioxidants can reduce the risk of an age-related vision problem called macular degeneration.

To see if the earlier study on chocolate could be repeated, Siedlecki and his team found 22 healthy volunteers, ages 20 to 62, who had good eyesight.

The volunteers were asked to eat either a 20-gram piece of dark chocolate or a 7.5-gram piece of milk chocolate. The piece of dark chocolate contained 400 milligrams of flavanoids, while the milk chocolate had about 5 milligrams of flavanoids.

Volunteers’ eyes were examined with a relatively⁵ new, high-tech⁶ scanner that shows blood vessels⁷ in detail. The volunteers were tested before they ate the chocolate and again two hours later.

Siedlecki’s team was looking for signs that the chocolate had enlarged⁸ blood vessels in the eye. This means volunteers were getting better blood flow.

Volunteers were also given low-technology vision tests similar to the ones used in the earlier chocolate study.

A week after the test, the people who got dark chocolate the first time were given milk chocolate, and those who had milk chocolate the first time were given dark chocolate.

The researchers said they found no difference in either test when volunteers ate dark chocolate or milk chocolate.

Doctor Gareth Lema was a little sad to read the latest findings⁹. “I like chocolate,” he explained.

While the new study failed to show any health benefit to eating a single piece of chocolate, “that doesn’t mean eating it over the long term isn’t beneficial,” said Lema. He works¹⁰ at the New York Eye and Ear Infirmary of Mount¹¹ Sinai in New York City.

“Neither study really showed that if you eat a piece of chocolate, you’ll have (great) vision,” Lema added.

Doctor Jay Chhablani agreed.

“Someone has to do a long-term study comparing dark chocolate to milk chocolate,” he said. Chhablani is an associate professor of ophthalmology at the University of Pittsburgh School of Medicine.

Both men know it will be easy to find volunteers.

I’m Susan Shand.

Words in This Story

chocolate – n. a food that is made from cacao beans and that is eaten as candy or added to other sweet foods

aspect – n. a quality, detail or part of something;

sample – n. a small amount of something that gives you information about the thing it was taken from

benefits – n. a good or helpful result or effect

scanner – n. a device¹² that reads or copies information or images into a computer

blood vessels – n. a small tube that carries blood to different parts of the body

1 lovers   

爱好者( lover的名词复数 )； 情人； 情夫； 情侣

参考例句：

• They were off-screen lovers. 他们是真实生活中的情侣。
• Shakespeare's star-crossed lovers, Romeo and Juliet 罗密欧和朱丽叶这一对莎士比亚笔下命运多舛的恋人

2 vision   

n.视觉，先见之明，光景，视力，眼力，幻想，影像；vt.幻想

参考例句：

• The wall cuts across our line of vision.那面墙挡住了我们的视线。
• Much reading has impaired his vision.大量读书损害了他的视力。

3 additional   

adj.添加的，额外的，另外的

参考例句：

• It is necessary to set down these additional rules.有必要制定这些补充规则。
• I think we can fit in an additional room.我想我们可以再加建一间房子。

4 publication   

n.出版，发行；出版；公布，发表

参考例句：

• They don't think this article is suitable for publication.他们认为这篇文章不宜发表。
• The government has delayed publication of the trade figures.政府已将贸易统计数字延后公布。

5 relatively   

adv.比较...地，相对地

参考例句：

• The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
• The operation was relatively painless.手术相对来说不痛。

6 high-tech   

adj.高科技的

参考例句：

• The economy is in the upswing which makes high-tech services in more demand too.经济在蓬勃发展，这就使对高科技服务的需求量也在加大。
• The quest of a cure for disease with high-tech has never ceased. 人们希望运用高科技治疗疾病的追求从未停止过。

7 vessels   

n.血管( vessel的名词复数 )；船；容器；（具有特殊品质或接受特殊品质的）人

参考例句：

• The river is navigable by vessels of up to 90 tons. 90 吨以下的船只可以从这条河通过。 来自《简明英汉词典》
• All modern vessels of any size are fitted with radar installations. 所有现代化船只都有雷达装置。 来自《现代汉英综合大词典》

8 enlarged   

扩大( enlarge的过去式和过去分词 )； 扩展； 扩充； 放大

参考例句：

• The balloon enlarged as we pumped air into it. 那个气球充气后就变大了。
• The castle was enlarged considerably in the fifteenth century. 这个城堡在15 世纪得到了相当大的扩展。

9 findings   

n.发现物( finding的名词复数 )；调查（或研究）的结果；（陪审团的）裁决

参考例句：

• It behoves us to study these findings carefully. 我们理应认真研究这些发现。
• Their findings have been widely disseminated . 他们的研究成果已经广为传播。

10 works   

n.作品，著作；工厂，活动部件，机件

参考例句：

• We expect writers to produce more and better works.我们期望作家们写出更多更好的作品。
• The novel is regarded as one of the classic works.这篇小说被公认为是最优秀的作品之一。

11 mount   

n.山峰，乘用马，框，衬纸；vi.增长，骑上（马）；vt.提升，爬上，装备

参考例句：

• Their debts continued to mount up.他们的债务不断增加。
• She is the first woman who steps on the top of Mount Jolmo Lungma.她是第一个登上珠穆朗玛峰的女人。

12 device   

n.器械，装置；计划，策略，诡计

参考例句：

• The device will be in production by the end of the year.该装置将于年底投入生产。
• The device will save much time and effort for us.这种装置会使我们节省大量时间和气力。