科学美国人60秒 通过咀嚼消耗的能量超乎想象(1)

This is Scientific American's 60-second Science, I'm Christopher Intagliata.

这里是科学美国人——60秒科学系列，我是克里斯托弗·因塔利亚塔。

When paleoanthropologists eat lunch with biomechanists...well, let's just say the small talk can get pretty technical.

当古人类学家与生物力学家共进午餐时……嗯，有时闲聊会变得专业。

Some of us would have cooked potatoes and other people would bring raw salads, they would just spend longer time chewing that food.

有些人会吃煮熟的土豆，有些人会吃生沙拉，这会让他们花更长时间来咀嚼食物。

This got us thinking about not just the temporal amount of time it takes to get through your food, but are they expending¹ more energy than those who are eating cooked food.

这让我们思考的不仅仅是吃完食物所花费的时间，还包括吃生食的人是否比吃熟食的人消耗更多的能量。

Adam Van Casteren of the University of Manchester says, luckily, there's a machine to measure that.

曼彻斯特大学的亚当·范·卡斯特伦表示，幸运的是，有一台可以测量的机器。

It's a clear chamber² you slip over your head -- looks like an astronaut's helmet.

这是一个可以带到头上的透明罩子——看起来像宇航员的头盔。

And it measures the oxygen you breathe in, versus³ the carbon dioxide you breathe out--a proxy⁴ for how much energy you're burning.

它可以测量吸入的氧气和呼出的二氧化碳--计算燃烧了多少能量。

Van Casteren and his colleagues got 21 volunteers to sit in that apparatus⁵ for 45 minutes, just to get a baseline on their metabolism⁶.

范·卡斯特伦和他的同事首先要求21名志愿者带着设备静坐45分钟，目的是为了测出他们的新陈代谢基准值。

Then, they gave them flavorless gum to chew on, for 15 minutes at a time.

然后，让他们咀嚼无味的口香糖，每次15分钟。

If you ever have to chew something for 15 minutes it's much longer than you think.

如果你不得不嚼某样东西15 分钟，那可比你想的时间要长得多。

And sometimes you have to remind people "keep chewing!"

有时我们不得不提醒志愿者“继续咀嚼!”

And boring is the key point here, I mean, like if you've chewed gum for way too long and it's lost its flavor and it's just this thing--that's what the participants were chewing.

“这里的关键是会无聊——口香糖嚼太久了，会失去味道，就是这个东西--这就是实验参与者咀嚼的东西。”

Co-author Amanda Henry of Leiden University in the Netherlands explained that, rather than cooked potatoes and raw salads -- they needed something with no taste or smell.

荷兰莱顿大学的合著者阿曼达·亨利解释说，参与者需要咀嚼没有味道或气味的食物，而非煮熟的土豆和生沙拉。

Because anything appetizing would set off a chain of digestive reactions.

因为任何开胃的东西都会引发一连串的消化反应。

Saliva⁷ and digestive juices would start flowing and that activity would swamp the metabolic⁸ measurements related to chewing.

唾液和消化液会开始流动, 这种活动会淹没与咀嚼相关的代谢测量。

And those measurements were significant -- turns out chewing a soft gum boosted the volunteers' metabolic rates by 10 percent above baseline.

这些测量值很重要--结果表明，咀嚼较软的口香糖可使志愿者的新陈代谢率比基准值高出10%。

A stiffer gum revved⁹ up metabolic rate by 15 percent.

较硬的口香糖使新陈代谢率提高了15%。

1 expending   

v.花费( expend的现在分词 )；使用（钱等）做某事；用光；耗尽

参考例句：

• The heart pumps by expending and contracting of muscle. 心脏通过收缩肌肉抽取和放出（血液）。 来自互联网
• Criminal action is an action of expending cost and then producing profit. 刑事诉讼是一种需要支付成本、能够产生收益的活动。 来自互联网

2 chamber   

n.房间，寝室；会议厅；议院；会所

参考例句：

• For many,the dentist's surgery remains a torture chamber.对许多人来说，牙医的治疗室一直是间受刑室。
• The chamber was ablaze with light.会议厅里灯火辉煌。

3 versus   

prep.以…为对手，对；与…相比之下

参考例句：

• The big match tonight is England versus Spain.今晚的大赛是英格兰对西班牙。
• The most exciting game was Harvard versus Yale.最富紧张刺激的球赛是哈佛队对耶鲁队。

4 proxy   

n.代理权，代表权；（对代理人的）委托书；代理人

参考例句：

• You may appoint a proxy to vote for you.你可以委托他人代你投票。
• We enclose a form of proxy for use at the Annual General Meeting.我们附上委任年度大会代表的表格。

5 apparatus   

n.装置，器械；器具，设备

参考例句：

• The school's audio apparatus includes films and records.学校的视听设备包括放映机和录音机。
• They had a very refined apparatus.他们有一套非常精良的设备。

6 metabolism   

n.新陈代谢

参考例句：

• After years of dieting,Carol's metabolism was completely out of whack.经过数年的节食，卡罗尔的新陈代谢完全紊乱了。
• All living matter undergoes a process of metabolism.生物都有新陈代谢。

7 saliva   

n.唾液，口水

参考例句：

• He wiped a dribble of saliva from his chin.他擦掉了下巴上的几滴口水。
• Saliva dribbled from the baby's mouth.唾液从婴儿的嘴里流了出来。

8 metabolic   

adj.新陈代谢的

参考例句：

• Impressive metabolic alternations have been undergone during embryogenesis.在胚胎发生期间经历了深刻的代谢变化。
• A number of intoxicants are associated with metabolic acidosis.许多毒性物质可引起代谢性酸中毒。

9 revved   

v.（使）加速( rev的过去式和过去分词 )；（数量、活动等）激增；（使发动机）快速旋转；（使）活跃起来

参考例句：

• The taxi driver revved up his engine. 出租车司机把发动机发动起来。
• The car revved up and roared away. 汽车发动起来，然后轰鸣着开走了。 来自《简明英汉词典》