TED演讲:碳水化合物是怎么作用于你的健康的(2)-英语课

时间：2019-01-17 作者：英语课 分类：TED演讲教育篇

英语课

　　Consider starch 1 and fiber 2, both polysaccharides, both derived 3 from plants, 拿淀粉和纤维来说，它们都是多糖，都是从植物中获得的，

　　both composed of hundreds to thousands of monosaccharides joined together, 也都由成百上千个单糖连接而成，
　　but they're joined together differently, and that changes the effect they have on your body. 但是它们的连接方式不同，这就改变了它们对你身体的影响。
　　In starches 4, which plants mostly store for energy in roots and seeds, 淀粉，是植物通常在根或者种子中存储能量的形式，
　　glucose 5 molecules 6 are joined together by alpha linkages, 葡萄糖分子是α键连接在一起的，
　　most of which can be easily cleaved 7 by enzymes 8 in your digestive tract 9. 大部分这种键可以很容易被你消化道中的酶断开。
　　But in fiber, the bonds between monosaccharide molecules are beta bonds, which your body can't break down. 但是在纤维中，单糖分子之间的键是β键，你的身体不能分解它。
　　Fiber can also trap some starches, preventing them from being cleaved, resulting in something called resistant 10 starch. 纤维也可以捕捉到一些淀粉，避免其被分解，生成一些被称为抗性淀粉的东西。
　　So foods high in starch, like crackers 11 and white bread, are digested easily, 因此淀粉含量高的食物，比如薄脆饼干和白面包，就很容易消化，
　　quickly releasing a whole bunch of glucose into your blood, 快速地释放大量葡萄糖到你的血液里，
　　exactly what would happen if you drank something high in glucose, like soda 12. 就好比你喝了一些葡萄糖含量高的饮料，比如苏打水。
　　These foods have a high glycemic index, the amount that a particular food raises the sugar level in your blood. 这些食物都有很高的血糖指数，也就是某一种食物升高血糖含量的数值。
　　Soda and white bread have a similar glycemic index because they have a similar effect on your blood sugar. 苏打水和白面包有相似的血糖指数，因为它们对你的血糖含量有相似的影响。
　　But when you eat foods high in fiber, like vegetables, fruits, and whole grains, 但是当你吃富含纤维的食物，比如蔬菜、水果，还有全麦时，
　　those indigestible beta bonds slow the release of glucose into the blood. 那些难消化的β键会减慢葡萄糖释放到血液中的过程。
　　Those foods have a lower glycemic index, and foods like eggs, cheese, and meats have the lowest glycemic index. 那些食物的血糖指数就低一些，像鸡蛋、奶酪还有肉这些食物的血糖指数就是最低的。
　　When sugar moves from the digestive tract to the blood stream, 当糖从消化道进入到血管中时，
　　your body kicks into action to transfer it into your tissues where it can be processed and used for energy. 你的身体就会开始将糖转运到身体组织中，在这里糖会被处理生成能量。
　　Insulin, a hormone 13 synthesized in the pancreas, is one of the body's main tools for sugar management. 胰岛素，一种在胰腺中合成的荷尔蒙，是身体中一种主要的血糖管理工具。