9-15 为什么水果和蔬菜是健康的首选？（在线收听）

Why Fruit and Vegetables Are the Tops for Good Health?

They used to say an apple a day keeps the doctor away. And according to the Department of Health, years of research shows that eating fruit and vegetables reduces the risk of many life-threatening diseases and helps us keep fit.

Coronary heart disease¹ (CHD) and strokes are major causes of death in the UK, yet a diet high in fruit and vegetables significantly reduces the risk of both. A recent study found that every extra portion of fruit and vegetables will lower your risk of CHD by four percent, and of strokes by six percent. Fruit and vegetables reduce the risk of some cancers, too, including colon² and stomach cancer. And alpha-carotene³ and lycopene⁴, found in high amounts in carrots and tomatoes, may help protect against lung cancer.

One of the main reasons fruit and vegetables are so health-boosting is that they’re packed with antioxidants⁵. Oxidization⁶ is what happens when harmful cells destroy cells. Free radicals⁷ are produced mainly by the body burning oxygen, partly as a result of smoking, pollution and sunlight. It’s these cells that cause your body and mind to age, and trigger a range of diseases.

Antioxidants are the chemicals that neutralize free radicals: the best known include beta carotene⁸ and selenium⁹ and vitamins A, C and E. Antioxidants are also found in some minerals, including calcium and iron, which are essential for protecting against the bone disease osteoporosis¹⁰, as well as helping to maintain a healthy nervous system.

Fruit and vegetables also contain phytonutrients, which work in the same way as antioxidants to benefit health. And, as if that wasn’ t enough, they can help you maintain a healthy weight because they increase your fiber intake, keeping you feeling fuller for longer and making you less likely to want to snack.

It’s easy to fit the foods you need into everyday life. For example, each of the following equals one portion: half a grapefruit, a medium tomato with a sandwich, and a medium banana. Fruit juice counts, but only as one portion due to it lacking the fibre content of whole fruit and vegetables. For maximum benefit, think in terms of “rainbow foods” eat a multi-colored range such as plums, broccoli, peppers, cherry tomatoes, cherries, tomatoes and pineapple juice.

Not everything has to be fresh either. Dried and canned fruits are a great standby¹¹, while frozen product often has a higher vitamin content than something that’s been kept in your fridge. So use fresh ingredients regularly, as well as having dried, canned and frozen foods to hand¹².

Some of us think we’re eating enough fruit and vegetables, but it can be confusing to work out which foods count, and how big a portion is. A portion actually equals 80g. An adult should be eating at least five portions of fruit and vegetables a day and children should also eat at least five portions a day, but they can be smaller.

Below suggests the right daily amounts for the average adult:

150ml pineapple juice

3 heaped tbsp cooked carrots

3 heaped tbsp cooked peas

half pepper

1 medium tomato

7 cherry tomatoes

80g watercress

2 medium plums

2 small tangerines

1 medium banana

4 heaped tbsp blueberries

3 dried apricots

1 heaped tbsp sultanas

注释：

1. coronary [5kCrEnEri] a. [解] 心脏冠状动脉（或静脉）的；a～ heart disease [医] 冠状动脉心脏病

2. colon [kEu5lEun] n. [解] 结肠

3. carotene [5kArEti:n] n. [生化] 胡萝卜素

4. lycopene [5laikE7pi:n] n. [生化] 番茄红素

5. antioxidant [5Anti5CksidEnt] n. [化] 抗氧（化）剂，阻氧化剂

6. oxidization [7Cksidai5zeiFEn] n.=oxidation[化]氧化（作用）

7. free radical [化] 自由基，游离基

8. beta carotene [生化] β- 胡萝卜素

9. selenium [si5li:niEm] n. [化] 硒

10. osteoporosis [7CstiEupC:5rEusis] n. [医] 骨质疏松（症）

11. standby [5stAndbaI] n. 受人喜爱的（或可靠的）常备物，备用品

12. to hand 近在手边，在手中

为什么水果和蔬菜是健康的首选？

过去人们常说，每天一苹果，不用找医生。根据(英国)卫生部报道，多年调查显示，食用水果和蔬菜会减少患很多致命疾病的危险，并有助于我们保持身体健康。

在英国，冠心病和中风是主要的死亡原因，但含大量水果和蔬菜的饮食会明显减少患这两种疾病的危险。最近的一项研究发现，每多食一份水果和蔬菜会使患冠心病和中风的危险分别下降4％和6％。水果和蔬菜还会减少患上某些癌症的危险，包括结肠癌和胃癌。胡萝卜和西红柿中的大量α-胡萝卜素和番茄红素有助于预防肺癌。

水果和蔬菜能促进健康的主要原因之一是，它们含有丰富的抗氧化剂。氧化作用是在有害细胞损坏正常细胞的时候发生的。游离基主要是在身体消耗氧气时产生，部分是因吸烟、污染和日照所致。正是这些有害细胞使得你的身体和精神老化，并引发一系列疾病。

抗氧化剂是可以对游离基进行中和的化学物质，其中最有名的包括β-胡萝卜素、硒以及维生素A、C和E。此外，一些包括钙和铁在内的矿物质中也含有抗氧化剂。钙和铁在防止骨质疏松症和帮助维持神经系统的健康方面都是必不可少的。

水果和蔬菜中还含有植物营养成分，它们和抗氧化剂一样有益于健康。不仅如此，它们还可以帮助你保持正常的体重，因为它们会增加你的纤维摄入量，从而使你在较长时间内没有饥饿感，减少了吃零食的欲望。

日常生活中合理食用所需的食物是一件容易的事情。比如，以下每份食物相当于一份摄入量：半个葡萄柚、一个中等西红柿和一块三明治、一根中等香蕉。水果汁也有效果，但因为它缺少整个水果和蔬菜的纤维成分，所以只能算作一份摄入量。为了最大限度增进健康，可以考虑食用所谓的“彩虹食品”，也就是食用各种颜色的水果或蔬菜，如李子、花椰菜、甜椒、圣女果、樱桃、番茄和菠萝汁。

不一定所有食物都必须是新鲜的。干果和罐头水果也是很好的备选食品，而冷冻食品通常比某些冷藏食品更富含维生素。所以人们不仅要常食用新鲜食物，还要备有脱水、罐装和冷冻食物。

我们中的一些人自认为每天食用的水果和蔬菜已经足够多了，但是却弄不清哪种食物有用以及食用量应是多少。一份摄入量实际上相当于80克。一个成年人每天的水果和蔬菜摄入量至少应为5份。儿童也应该每天摄入同样的份数，但可以减量。