爲什麼感覺疲勞的時候特別想吃垃圾食品?

Demolishing half a packet of biscuits while staying up trying to finish an assignment, swapping fruit for a chocolate bar for your snack at work after an early start or longing for a croissant upon landing from a long-haul flight, there could now be a reason why you reach for the bad food after a bad night's sleep.
在熬夜辦公時，你是否會輕而易舉地消滅半包餅乾？早起之後，你是否會把工作間餐的水果換成巧克力？或者是乘坐長途飛機後特別想要吃牛角麪包？對於爲什麼晚上睡眠不好、白天就會想吃垃圾食品這個問題，這裏可能會給你一種解釋。

Researchers at Feinberg School of Medicine, Northwestern University in Chicago recently presented their results of a study looking into the effects of sleep deprivation upon high-calorific food consumption at the Cognitive Neuroscience Society's annual meeting in San Francisco, reports Science News.
最近，在洛杉磯的認知神經科學學會年度會議上，來自西北大學費恩伯格醫學院的研究者們發表了關於缺乏睡眠對高熱量食物攝入的影響的研究報告。

Participants were allocated different amounts of sleep, eight hours or four hours, and then their reaction to smells of high-calorific foods were tested.
這次試驗中，參與者睡眠的時間各不相同，可能是8小時或4個小時，隨後測試他們對於高卡路里食物的味道的反應。

Participants slept for both lengths of time, separated by a week of normal sleep.
每一位參與者都要參與這兩種不同時長的睡眠實驗，兩次試驗間隔一週的正常作息。

On the day after they either had full or partial sleep, participants rated the pleasantness and intensity of sweet and savoury high-calorific food smells such as crisps and cinnamon rolls. They were then asked to rate the smell of non-foods like fir trees.
在他們參加睡眠實驗的第二天，參與者們被要求對包括薯片和肉桂卷這樣的高糖、高鹽、高卡路里食物打分，研究這些食物是否吸引人，能否讓人感到愉悅。隨後，參與者被要求給松木等非食品的氣味打分。

Researchers found that those who were sleep-deprived had "specifically enhanced" brain activity to the food smells compared to when they had a good night's sleep.
研究人員發現，相較於睡眠充足的人，缺乏睡眠的人對於食物的氣味有“強烈的”腦部活動。

The experiment supports the long-held association between sleep deprivation and excessive eating and weight gain.
這項實驗論證了人們長久以來相信的缺乏睡眠和暴飲暴食、體重增加之間的關係。

So, if you want to stop reaching for the chocolate every day, perhaps a few extra hours sleep is all you need.
所以，如果你想要戒掉每天必吃的巧克力，你可能只需要額外幾個小時的睡眠就可以了。