什麼時間吃和吃什麼一樣重要大綱

We all know that eating badly, and eating too much, are associated with gaining weight. New research has shown that another factor is also important -what time of day you eat. A new study, published in The American Journal of Clinical Nutrition, showed that eating later in the evening was associated with a higher percentage of body fat.

我們都知道：吃的差和吃的多都會導致體重增加。新研究已表明，另一個因素同等重要--每天什麼時候吃。《美國臨牀營養雜誌》上刊出的一項新研究表明，晚上稍晚一點吃東西與更高的體脂比例相關。

But it also found that the overall effects all came down to your own personal biological clock rather than the actual time. Researchers collected data from 110 college students over 30 days to observe their sleep times and eating habits. They also looked at when subjects released melatonin - the sleep hormone - to determine where their circadian rhythms (body clocks) were at.

但研究還發現整體影響因素得歸結於個人的生物鐘，而不是實際時間。研究人員在30天內收集110名大學生的數據，以觀察他們的睡覺時間和飲食習慣。他們還觀察了受試者何時釋放褪黑激素--睡眠激素--以確定他們的晝夜節律（身體時鐘）。

They then examined the relationship between body clock setting, body mass index (BMI), and the timing of food consumption. The team expected to see that individuals who ate closer to their melatonin onset - which is usually occurs just before sleep - would have a higher percentage of body fat.

之後他們檢查了身體時鐘設定、身體質量指數和進食時間的關係。該團隊估計，臨近褪黑激素釋放點吃東西的人--通常在睡覺之前--會有更高的體脂比例。

Results showed that they were right, and those who had high body fat percentages consumed most of their calories shortly before going to bed, when melatonin levels were high. However, this didn't mean they found a relationship between eating later and gaining weight per se, rather that timing of when you consume calories, relative to your own biological timing, may be an important factor for your health.

研究結果表明他們的猜測是正確的，那些體脂比例高的人大多數的熱量都是在睡前攝入的，那時的褪黑激素是最高的。然而，這並不意味着他們發現了吃的晚與體重增長本身的關係，而是發現了什麼時候攝入熱量，與自己的生物鐘相比較，可能是影響健康的重要因素。

"We believe that our findings highlight that when you eat may be just as important as what you eat," lead author Andrew W. McHill, researcher with the Division of Sleep and Circadian Disorders at Brigham and Women's Hospital in Massachusetts, told Business Insider.

"我們認爲我們的研究強調了什麼時候吃可能與吃什麼一樣重要，"首席作者安德魯W.麥克希爾對Business Insider雜誌說道，他還是馬薩諸塞州婦女醫院和布里格姆Sleep and Circadian Disorders部門的研究員。

"We actually hypothesise that the mechanism driving this result is a lower amount of energy expended to break down food that is consumed during the night, as we have shown that to be true during controlled laboratory studies."

"我們實際上假設導致這一結果的機制是夜晚攝入食物時，分解食物的能量更低，在控制實驗研究中，這一假設被證明是正確的。"

As with every study, there were a few limitations, such as the fact that participants may have under-reported how many calories they consumed, or may have changed their eating habits while they knew they were being tracked.

每一項研究都有一些限制，比如受試者可能少報了他們攝入的熱量，或者可能在知道自己被追蹤的情況下改變了自己的飲食習慣。

There was also only one night where melatonin levels were assessed, so slight changes could not be identified.

同時，我們只在一個晚上評估了褪黑激素水平，所以無法確定輕微的變化。