為什么你明明不餓，卻總想吃東西？科學(xué)解釋來了！

Have you ever wondered why some days all you want to do is snack?

不知道你有沒有想過這個(gè)問題：為什么有時(shí)候你會不停地想吃東西?

Under normal circumstances, we feel hungry when we have burnt up the food we have eaten as energy and our blood sugar and insulin levels begin to drop. Ghrelin, a hormone connected to appetite, then communicates this to the brain, which is how we feel the need to eat.

在正常情況下，當(dāng)身體把食物轉(zhuǎn)為能量消耗掉之后，我們的血糖和胰島素水平也開始降低，這時(shí)我們就會感到饑餓。然后，饑餓激素將這個(gè)信息傳達(dá)給大腦。這樣我們就會感覺到需要吃東西了。

insulin：胰島素

Ghrelin：/?ɡr?l?n/食欲刺激素

But all sorts of things can interfere with this process.

但是各種各樣的事情都會干擾這個(gè)過程。

1 When you are tired

According to a 2011 study by researchers at Columbia University in the US, those who are sleep-deprived eat almost 300 calories a day more than those who get enough sleep.

根據(jù)美國哥倫比亞大學(xué)2011年研究人員的一項(xiàng)研究，那些睡眠不足的人每天攝入的熱量幾乎比那些睡眠充足的人多300卡路里。

This is because levels of the hormone ghrelin, which tells the brain we need to eat, increase when we don't get enough sleep.

這是因?yàn)楫?dāng)我們沒有足夠的睡眠時(shí)，饑餓激素會增加，會告訴大腦需要吃更多的東西。

The Columbia researchers noted that the women who didn't get enough sleep took in more fat rising by around 30g on sleep-deprived days — four times as much as the average increase for men.

哥倫比亞大學(xué)的研究人員指出，睡眠不足的女性在睡眠不足的日子里攝入的脂肪增加了約30克。這是男性平均增加量的四倍。

2 Troubled times

In a 2013 study, people who were primed to expect "tough times ahead" ate more food than people who listened to neutral messages.

在2013年的一項(xiàng)研究中，那些得知不久會遇到“艱難時(shí)期”的人會比獲得中性信息的人吃更多的食物。

primed：準(zhǔn)備好的

It's thought that hearing about troubled times causes a survival instinct to kick in, leading to cravings for high-calorie snacks such as chocolate.

一聽說“有麻煩了”，人的生存本能就被激發(fā)了，對巧克力等高熱量零食的渴望也隨之增加。

3 'Naughty' food cravings

Tempted by that extra biscuit? Then just enjoy it — as researchers have found that when you feel guilty about a pleasurable experience, the guilt itself becomes pleasurable, so encouraging you to do it more.

還想再吃一塊小餅干?吃就吃吧，開心一點(diǎn)。研究人員發(fā)現(xiàn)，當(dāng)你對某個(gè)愉快的體驗(yàn)感到內(nèi)疚時(shí)，內(nèi)疚本身也會帶來快感，進(jìn)而鼓勵(lì)你再次去做這件事。

"If we consider something a naughty pleasure, it can psychologically drive the appetite and the guilt may make you want to eat more," says Cary Cooper, at the University of Lancaster.

蘭卡斯特大學(xué)的Cary Cooper說，如果我們認(rèn)為某件事會帶來不守規(guī)矩的快感，它會在心理上促進(jìn)食欲，而這種內(nèi)疚可能會讓你想要吃更多。

The appetite center of the brain also lies very close to the area governing mood — the limbic system — which is why changes in the way we feel may affect appetite.

大腦中的食欲控制區(qū)域非常接近情緒控制區(qū)域——邊緣系統(tǒng)——這就是為什么我們的情緒變化會影響食欲。

limbic：邊緣的

4 Mobiles' blue light

The bright blue light emitted by devices such as smartphones and tablets may give an unwelcome boost to your appetite.

智能手機(jī)和平板電腦等設(shè)備發(fā)出的藍(lán)光可能會增進(jìn)飲食。

Research this year found that your appetite continued to increase when you are exposed to the light.

今年的研究發(fā)現(xiàn)，藍(lán)光下你的食欲會持續(xù)增加。

It also altered people's metabolism, as blood tests showed that the blue-light subjects had higher insulin and glucose levels.

藍(lán)光的照射還會改變?nèi)藗兊男玛惔x。血液測試顯示，接受藍(lán)光受試者的胰島素和葡萄糖水平都更高。

metabolism /m?'tæb?l?z?m/：新陳代謝

glucose /'ɡlukos/：葡萄糖

One possible explanation is that bright blue light at night confuses our body clock, which has a role in controlling when we feel the need to eat.

一種可能的解釋是，夜間明亮的藍(lán)光會干擾我們的生物鐘。而生物鐘可以控制我們什么時(shí)候覺得需要進(jìn)食。

不知道今天的文章有沒有解決你的疑問呢?