吃胡萝卜真的可以帮助保护视力吗？保护和提高视力的秘密到底是什么？吃保健品或多吃某些食物能有帮助吗？研究显示人们可以通过食用含有叶黄素的膳食补充剂来提高视力。叶黄素可以保护视网膜免受有害光线的损伤。本期《随身英语》介绍对人眼和视力有益的食物。

课文内容

Do carrots really help you see in the dark? What about kiwis or kale? Can eating certain foods improve your eyesight or prevent your eyes degenerating? Perhaps we should all be taking supplements to benefit our vision? Research in both the US and Ireland has shown that supplementing the diet with certain key chemicals can significantly benefit your vision. These can be taken as supplements but they are also found widely in many green leafy plants and green and yellow fruit and vegetables.

The retina is the part of our eye that contains cells sensitive to light. The most delicate area of this tissue – the macula – is protected from harmful blue and UV light by yellowish ‘macular pigment’. This acts like sunglasses, blocking the damaging light. It comprises three pigments – lutein, zeaxanthin and meso-zeaxanthin.

A research team led by Professor Nolan in Ireland has recently completed a year-long trial investigating the benefits of taking supplements of macular pigments. 100 participants took part in the experiments. The results showed that by taking lutein, zeaxanthin and meso-zeaxanthin, there was a significant improvement in the protection of the macula, as well as in overall eyesight. There was also some evidence that these chemicals can help to slow down macular degeneration, which is the main cause of sight loss in the UK. However, this is somewhat controversial.

Lutein is a yellow compound found only in plants, which produce it to absorb light. We can get lutein by eating foods like kale and spinach. It is also present in egg yolk. Zeaxanthin, another yellow compound similar to lutein, is found in such foods as corn, yellow bell peppers and saffron. Meso-zeaxanthin is not generally found in food sources, though it can be found in some fish. It is created in the retina from ingested lutein. It can be taken in supplements made with marigold extracts.

As for carrots, it turns out that it’s the leafy green bits on the top that contain the key compounds beneficial to eyesight, rather than the vegetable itself. So next time you’re told carrots help you see in the dark, save them for the rabbit and chop up some kiwi instead!

词汇表

kale （蔬菜）羽衣甘蓝
to degenerate 下降，衰退
supplement 补充物，补充片剂
chemical 化学品
vision 视力
retina 视网膜
tissue 组织
macula 视网膜黄斑
pigment 色素
lutein 叶黄素
zeaxanthin 玉米黄素
meso-zeaxanthin 消旋玉米黃素
sight loss 失明
compound 化合物
saffron 藏红花
to ingest 摄取
marigold extract 万寿菊提取物

测验与练习

1. 阅读课文并回答问题。 

1. True or false? Eating yellow and green vegetables can be harmful to your eyesight. 

2. What is the macula? 

3. How does macular pigment protect the macula?

4. Name two food sources of lutein.        

5.  Why does the writer of the article conclude that there isn’t much point eating carrots if you want to see in the dark? 

2. 请你在不参考课文的情况下完成下列练习。选择一个意思合适的单词填入句子的空格处 。

1. The retina in the eye contains cells that are _________ to light.

sensible            sensitive            sensuous               sensational

2. She knew that his eyesight had seriously begun to _________ when she couldn’t read the label on the packet.

generate          decompose         degenerate       disintegrate

3. The five-week course of dietary supplements led to _________ improvement in the participants’ vision.

beneficial            large               big                  significant

4. A healthy balanced meal consists _________ plenty of vegetables, some protein and a little carbohydrate.

 in          of       with        on       

5. It’s an old wives' tale that carrots help _________ in the dark!

you to see       you seeing         to see you         you to seeing

答案

1. 阅读课文并回答问题。

1. True or false? Eating yellow and green vegetables can be harmful to your eyesight.
False. Some yellow and green vegetables contain chemicals that are beneficial to eyesight.     

2. What is the macula? 
It’s the delicate part of the retina in the eye.   

3. How does macular pigment protect the macula?
It blocks the damaging blue and UV light.

4. Name two food sources of lutein.
Two from: kale, spinach, egg yolks                  

5. Why does the writer of the article conclude that there isn’t much point eating carrots if you want to see in the dark?  
Because it’s the leafy green part on top of the vegetable that contains the compounds beneficial to eyesight, and not the vegetable itself.

2. 请你在不参考课文的情况下完成下列练习。选择一个意思合适的单词填入句子的空格处 。

1. The retina in the eye contains cells that are sensitive to light.

2. She knew that his eyesight had seriously begun to degenerate when she couldn’t read the label on the packet.

3. The five-week course of dietary supplements led to significant improvement in the participants’ vision.

4. A healthy balanced meal consists of plenty of vegetables, some protein and a little carbohydrate.

5. It’s an old wives' tale that carrots help you to see in the dark!