(单词翻译:单击)
It’s happened to all of us.
我们所有人都有过这样的经历。
Dinner’s over and you’re stuffed.
晚餐结束了，你吃饱了。
But then someone brings out the pie and ice cream.
但后来有人拿出馅饼和冰淇淋。
And while a moment ago you couldn’t have eaten another bite, suddenly…
刚才你还不能再吃一口，
well, of course you can find room for a little pie.
突然，你能腾出地方吃一点派。
And it’s actually kind of true that you always have room for dessert.
事实上，你总能给甜点留出点地方。
It has to do with how our bodies evolved—long before dessert existed the way we know now.
这与我们的身体进化有关，远早于甜点出现的时间。
But once you understand why you always have room for dessert,
一旦你明白了为什么总有地方吃甜点，
you’ll see how you can use this weird quirk of your appetite to your advantage.
你就知道如何利用胃口这个奇怪的怪癖了。
When it comes to our appetites in general, humans and other animals tend to get less pleasure
总的来说，谈到我们的食欲时，人类和其他动物往往吃得越多，
out of eating something the more they eat it.
从中获得的快乐就越少。
This is called sensory specific satiety, and it’s an example of habituation.
这就是所谓的感官特异性饱腹感，这是一个习惯化的例子。
Whenever you encounter some stimulus over and over again, your response to it goes down.
当你一次又一次地遇到一些刺激，你对它的反应就会下降。
It’s like when you hear a great new song for the first time, and you love it—
就像当你第一次听到一首很棒的新歌，会很喜欢它。
but then after a few months of hearing it on the radio, you’re just completely over it.
但是在收音机里听了几个月之后，你就听腻了。
Our brains react the same way to food.
我们的大脑对食物的反应也一样。
At first, a new food is really rewarding… but eventually, your brain gets tired of it.
一开始，一种新的食物非常好吃。但最终，大脑会对它感到厌倦。
And neuroscientists have actually watched that happen in real time.
神经科学家已经实时观察到了这种情况。
In a 2001 study published in the journal Brain,
001年发表在《大脑》杂志上的一项研究中，
experimenters gave nine subjects a series of chocolates and scanned their brains while they ate them.
2实验者给9名受试者一系列巧克力，并在他们吃巧克力时扫描他们的大脑。
After every piece, the subjects rated how much they enjoyed the snack and how much they wanted another.
每吃完一块，受试者都会对他们对巧克力的喜欢程度和想继续吃的欲望进行评分。
Even though they were eating the same kind of chocolate each time,
尽管他们每次吃的是同一种巧克力，
both of these ratings kept going down with every passing piece.
但对这两种巧克力的评分随着进一步的进食而不断下降。
Not only that, but their brain activity changed, too —
不仅如此，他们的大脑活动也发生了变化——
specifically in the orbitofrontal cortex, which processes sensory and emotional information.
特别是在处理感官和情感信息的眼眶额叶皮质。
In one spot, there was less activity over time, suggesting it was reacting to how rewarding the chocolate was.
在一个地方，随着时间的推移，其活动减少，这表明它对巧克力的好吃程度作出反应。
But in another spot there was more activity, suggesting that it was a sign of an increased sense of revulsion or punishment.
但在另一个地方则有更多的活动，表明它表现出厌恶感或惩罚感的增强。
To chocolate.
对巧克力的感觉。
Because it had just had enough.
因为已经吃够了。
And a number of studies have shown similar results
许多研究也显示出类似的结果。
When people fill up on one thing, even if it’s something they like, they begin to feel repulsed by it.
当人们对一件事充满热情时，即使是喜欢的东西，也会开始感到厌恶。
But even if they can’t stomach any more of that one thing, their brains don’t have the same reaction to other food.
但即使他们不能再忍受一种东西，大脑对其他食物也不会出现同样的反应。
So when it comes to finding room for dessert, something similar seems to be going on.
所以，在为甜点腾地方时，类似的事情似乎也在发生。
See, if you’ve had a well-balanced meal, you’ve probably filled up on vegetables, proteins, and complex carbs—so your body’s had enough of that.
你看，如果你吃了一顿营养均衡的饭，可能蔬菜、蛋白质和复合碳水化合物已经让你饱了，所以身体吃够了。
But dessert is different. It doesn’t have a lot of those things, and it usually has a lot more sugar.
但是甜点不同，它没有很多这样的东西，通常是更多的糖。
And your brain’s not tired of that yet, so suddenly, you’re not as full as you thought.
你的大脑还没有厌倦，所以突然间，你就没有想象的那么饱了。
As weird as that seems, it might have been kind of an advantage from an evolutionary perspective.
尽管这看起来很奇怪，但从进化的角度来看，这可能是一种优势。
We don’t know exactly why we evolved this trait, but in the past,
我们不知道为什么进化出这种特性，但在过去，
the fact that we sought out variety might have meant we were better at eating a balanced diet, and weren’t missing key nutrients.
我们寻找多样性的事实可能意味着均衡饮食对我们更好，使我们不缺少关键的营养物质。
There’s also one other factor that makes it especially easy to make room for dessert.
还有另外一个因素，让我们特别容易腾出地来吃甜点。
Dessert just doesn’t fill you up the same way as other food.
甜点并不像其他食物那样让你饱腹。
Typically, you know you’re hungry because your stomach releases a hormone called ghrelin,
通常，你知道自己饿了，因为胃会释放一种叫做饥饿荷尔蒙的激素，
which alerts the brain that you need food.
它提醒大脑需要进食。
Then as you eat, the amount of ghrelin in your blood goes down, and you start to feel less hungry.
进食时，血液中的饥饿荷尔蒙含量下降，你开始感觉不那么饿了。
But that change in the amount of ghrelin depends on what you’ve eaten.
但是饥饿荷尔蒙含量的变化取决于你吃了什么。
Complex carbs and proteins cause a significant drop, but sugar barely changes your ghrelin level at all.
复杂的碳水化合物和蛋白质会导致其显著下降，但是糖几乎不会改变饥饿荷尔蒙的水平。
Eating just simple sugars is almost as insignificant to your appetite as drinking water.
只吃糖对你的食欲几乎和喝水一样微不足道。
And let’s face it—most desserts are basically sugar.
面对现实吧，大多数甜点基本上都是糖。
So, not only is your brain not tired of it, but as you eat, dessert just doesn’t fill you up as much.
所以，不仅大脑不厌倦甜点，而且吃甜点时，也不会让你饱腹。
Your body does have other ways of informing you that it’s full,
身体确实有其他的方式告诉你吃饱了，
like by using special receptors to sense how stretched or contracted your stomach is, so eventually you would feel full no matter what.
比如通过用特殊的感受器来感知胃部的伸展或收缩，所以最终你会感觉到饱了。
But if you’re still feeling betrayed by your brain for letting you eat more dessert than you intended, think about it this way.
但是，如果你仍然觉得被大脑背叛了，因为它让你吃了更多的甜点，那么这样想吧。
You can also use all this to your advantage.
你也可以利用它。
For example, sensory-specific satiety does make it easier to squeeze in dessert,
例如，感官上的饱腹感确实更容易给甜点腾出地方，
but you can also take advantage of it to squeeze other foods into your diet.
但你也可以利用它在饮食中增加其他食物。
Like, maybe you bought something healthy for snacking, like a bag of almonds,
比如，也许你买了一些健康的零食，比如一袋杏仁，
but now you’re just tired of those, and the junk food is calling to you.
但是你吃腻了，想吃垃圾食品。
Well, if you have a variety of healthy snacks, you have a better chance of actually wanting to eat them.
如果你有各种各样的健康零食，就更有可能想吃它们。
In a 2013 study in American Journal of Clinical Nutrition, researchers tested a similar thing on kids.
2013年发表在《美国临床营养学杂志》的一项研究中，研究人员对儿童进行了类似的测试。
During preschool snack time, they put out different fruits and vegetables and tracked what the children ate.
在上学之前的小吃时段，他们拿出不同的水果和蔬菜，追踪孩子们吃了些什么。
If they just put out one kind of fruit or vegetable, about 70% of kids took a snack.
如果他们只拿出一种水果或蔬菜，大约70%的孩子吃零食。
But if they put out a variety, 94% did—and they ate about three more pieces of fruit on average.
但如果他们拿出很多种水果或蔬菜，94%的孩子平均多吃了大约三块水果。
So if you’ve ever struggled to get a picky kid to eat some vegetables, variety might help!
所以，如果你曾经努力让挑剔的孩子吃一些蔬菜，准备很多种类可能会有所帮助！
And when it is time for dessert, if you’re trying to scale back, you can try avoiding eating sugars on their own.
要吃甜点时，如果你想少吃点，可以试着避免只吃糖。
Like, you could have your ice cream with fruit or add oats to your cookies—and it may help you feel fuller for longer.
比如，你可以把冰淇淋和水果一起吃，或者在饼干里加燕麦，这样可以让你感觉更饱。
If nothing else, it’s good to know that it’s not your imagination.
知道这不是你的想象是件好事。
Your body really does react a little differently to dessert at the end of a meal.
身体对餐后甜点的反应确实有点不同。
And at the very least, knowing how it works might help you trick yourself to eating a little better.
至少，了解它的工作原理可以帮助你让自己吃得更好一点。
