Tiredness may lead to snacking
越困越想吃零食是怎么回事？
Staying up late doing homework is always tiring. And perhaps when we become tired, we feel the need to eat unhealthy snack food. Recently scientists have been investigating tiredness and snack food.
熬夜做作业总是让人精疲力尽。每当疲惫时，我们或许就想吃些不健康的零食。科学家们最近就调查了疲劳和零食之间的关系。
According to a study in the Journal of Neuroscience, people are more likely to crave snacks when they don't get enough sleep.
刊登于《神经科学期刊》上的一项研究表明，人们在睡眠不足时更想吃零食。
For the study, researchers from the University of Cologne in Germany gave the same dinner to 32 healthy men aged between 19 and 33. Half of the men were then sent home to bed, and the other half were kept awake in the laboratory all night.
为进行该项研究，来自德国科隆大学的研究者们为32名年龄在19-33岁不等的健康男子提供了同样的晚餐。其中，一半的人饭后回家休息，而另一半人则在实验室里彻夜未眠。
The next morning, the participants were asked to consider how much they would be willing to pay for snack food items shown to them in pictures.
第二天一早，研究人员向实验参与者们展示了一些零食的图片，并问他们愿意花多少钱来购买这些零食。
According to the researchers, all were similarly hungry in the morning, and had similar levels of most hormones and blood sugar.
研究人员认为，所有人当天早上的饥饿程度以及大多数激素和血糖的水平都是相似的。
However, brain scans showed that when the sleep-deprived participants looked at the pictures of junk food, they released more of the "hunger hormone". This is the hormone responsible for increasing the appetite, and making us consume more.
然而，根据脑部扫描检查显示，睡眠不足的参与者们在看到垃圾食品的图片时，会产生更多“饥饿激素”。这种激素能够增加食欲，让我们吃得更多。

Asked about how much they would pay for snacks, "participants with sleep deprivation were more willing to overspend on food items than those with a good night's sleep," researchers told Science Daily.
当被问及愿意花多少钱买零食时，“和好好睡了一觉的参与者相比，睡眠不足的参与者更愿意花更多的钱买零食，”研究人员们在接受《每日科学》网站采访时如此表示。
Researchers also observed that among the people who hadn't slept, there was greater activity in the part of the brain where food rewards are processed.
研究者们还观察到，在缺乏睡眠的人群当中，他们大脑处理食物奖励的部分会更加活跃。
The scientists think that sleep-deprived people experience changes to the hunger hormone and the brain's reward system that then leads to a stronger desire to eat snacks with high fat and calories.
科学家们认为，睡眠不足会让人们体内的饥饿激素水平和大脑奖励机制发生变化，从而让他们更想吃高脂肪、高热量的零食。
"This brings us a little closer to understanding the mechanism behind how sleep deprivation changes food valuation," Professor Jan Peters, a co-author of the study from the University of Cologne, told The Independent.
“这让我们更近一步明白了睡眠不足如何影响人们对待食物的机制，”该研究的合著者之一，来自科隆大学的扬·彼得斯教授在接受《独立报》采访时如此表示。