人生似乎就是在不斷地饑餓和吃飯飯而周而復始的，是時候搞清楚“一頓不吃餓得慌”背后的成因啦。節(jié)食失敗的同志有福啦。

Hunger claws at your grumbling belly. 

饑餓感正在你的腹中翻騰。 

It tugs at your intestines, which begin to writhe, aching to be fed. 

它撕扯著腸子開始扭動，渴望著食物。 

Being hungry generates a powerful, often unpleasant physical sensation that's almost impossible to ignore. 

饑餓會產生一種強烈的身體不適感，讓人根本無法置之不理。 

After you've reacted by gorging on your morning pancakes, 

消化完早上吃的煎餅后，

you start to experience an opposing force, fullness, 

你就會體驗到相反的感覺——飽腹感， 

but how does your body actually know when you'r full?

但是你的身體怎么知道你飽了？ 

The sensation of fullness is set in motion as food moves from your mouth down your esophagus.

當食物從嘴下咽進入食道，飽腹感就開始產生了。

Once it hits your stomach, it gradually fills the space.

食物一旦進入胃逐漸填滿胃內空間。

That causes the surrounding muscular wall to stretch, expanding slowly like a balloon.

胃壁就如同氣球一樣，開始慢慢膨脹。

A multitude of nerves, wrapped intricately around the stomach wall, sense the stretching.

胃壁上的神經能感受到胃壁的擴張。 

They communicate with the vagus nerve, up to the brain stem and hypothalamus,

這些神經同迷走神經相連，到達腦干和下丘腦，

the main parts of the brain that control food intake.

即大腦中控制食物攝入量的部分。

But that's just one input your brain uses to sense fullness.

不過這還只是飽腹感其中的一項。 

After all, if you fill your stomach with water, you won't feel full for long.

畢竟 如果你只是喝水來灌滿你的胃，也不會長時間感到飽腹的。 

Your brain also takes into account chemical messengers in the form of hormones produced by endocrine cells throughout your digestive systems.

大腦還要聽取化學信使的報告，它們是由消化系統(tǒng)內分泌的細胞分泌的激素 。

These respond to the presence of specific nutrients in your gut and blood stream which gradually increase as you digest your food.

這些響應于腸道和血液的特定營養(yǎng)素，會隨著消化食物逐漸增加。

As the hormones seep out, they're swept out by the blood and eventually reach the hypothalamus in the brain.

細胞分泌激素后進入到血液中，最后隨血流到下丘腦中。 

Over 20 gastrointestinal hormones are involved in moderating our appetites.

超過20種的激素參與了食欲調節(jié)的過程 。

One example is cholecystokinin which is produced in response to food by cells in upper small bowel.

其中一個例子就是腸促胰酶肽，它是上腸細胞和食物反應后產生的。 

When it reaches the hypothalamus,

這種激素到達下丘腦之后，

it causes reduction in the feeling of reward you get when you eat food.

就會減少人在進食時獲得的獎勵感。 

When that occurs, the sense of being satiated starts to sink in and you stop eating.

這過程一旦開始，滿足感就會下降，人也會停止進食。 

Cholosystokinin also slows down the movement of food from the stomach into the intestines.

腸促胰肽酶還會減慢食物從胃部到腸道的運動。 

That makes your stomach stretches more over a period of time,

讓你的胃在一段時間內擴張得更大，

allowing your body to register that you're filling up.

讓身體知道已經吃下這么多食物了。 

This seems why when you eat slowly you actually feel fuller compared to when you consume your food at lightning speed.

這就是為什么吃慢時比吃快時更容易感到飽的原因。

When you eat quickly, your body doesn't have time to recognize the state it's in.

吃快的時候，你的身體還來不及搞清楚狀況。 

Once nutrients and gastrointestinal hormones are present in the blood,

血液中一旦出現(xiàn)了營養(yǎng)物質與腸胃激素，

they trigger the pancreas to release insulin.

就會促發(fā)胰腺釋放出胰島素。 

Insulin stimulate the body's fat cells to make another hormone called leptin.

胰島素會刺激身體的脂肪細胞生成瘦素。 

Leptin reacts with receptors on neuron populations in the hypothalamus.

瘦素會與下丘腦的神經元群受體反應 。

The hypothalamus has two sets of neurons important for our feeling of hunger.

下丘腦有兩套對于饑餓感而言相當重要的神經元。 

One set produces the sensation of hunger by making and releasing certain proteins.

其中一套通過生成和釋放特定的蛋白質制造饑餓感。 

The other set inhibits hunger through its own set of compounds.

另一套則通過另一套化合物來抑制饑餓感。 

Leptin inhibits the hypothalamus neurons that drive food intake and stimulates the neurons that suppress it.

瘦素會抑制下丘腦中控制食物攝入的神經元，并刺激抑制食物攝入的神經元。

By this point, your body has reached peak fullness through the constant exchange of information between hormones,

這時通過不同部位間的激素交換，你的身體就達到了飽腹感的頂點， 

the vagus nerve, the brain stem and the different portions of hypothalamus,

通過不同部位間的激素交換，比如迷走神經、腦干、下丘腦的不同部位，

you brain gets the signal that your brain has eaten enough. 

大腦就會接收到已經吃飽的信號。 

Researchers have discovered that some foods produce more long-lasting fullness than others.

調查人員發(fā)現(xiàn)，某些食物會比其他食物產生更久的飽腹感。 

For instance, boiled potatoes are ranked as some of the most hunger-satisfying foods.

比如煮土豆，位于最能形成飽腹感的食物之列。 

While croissants are particularly unsatisfying.

而羊角面包則是最無法形成飽腹感的食物。 

In general, foods with moe protein, fiber and water tend to keep hunger at bay for longer.

通常蛋白質、纖維素和水分含量高的食物能更長時間驅除饑餓感。 

But feeling full won't last forever.

然而飽腹感并不會維持很久。 

After a few hours, your gut and brain begin their conversation again.

幾個小時后，身體器官和大腦又會開始對話。 

Your empty stomach produces other hormones, such as ghrelin,

空腹又會產生其他的激素，例如饑餓激素 ，

and increase the the activity of hunger-causing nerve in the hypothalamus.

它會增加下丘腦內引起饑餓感的神經元的活性。 

Eventually, the growling beastt of hunger is reawakened.

咆哮的饑餓之獸最終覺醒。 

Lucklily, there's a dependable antidote for that.

幸運的是，還有可以對付它的可靠的解藥。