對(duì)于現(xiàn)代人，一般來(lái)說(shuō)，早、中、晚三餐時(shí)間大約定在7:30、12:30、18:30。當(dāng)然，由于生活軌跡和個(gè)人習(xí)慣的不同，每個(gè)人的三餐時(shí)間自然有所差異。那么晚點(diǎn)吃飯到底為啥不好？不也是一天三頓嗎？

近日，一項(xiàng)發(fā)表在《細(xì)胞代謝》雜志的最新研究給出了明確回答：吃飯時(shí)間真的很重要！更晚地吃飯（如一天三頓的攝入時(shí)間比別人遲4個(gè)小時(shí)），會(huì)從三大方面誘發(fā)肥胖：增加食欲、降低能量消耗、改變脂肪組織基因的表達(dá)。吃太晚真的容易長(zhǎng)胖，快把“時(shí)差”倒回來(lái)！

We all know that eating later in the day isn’t good for our waistlines, but why? A new study weighed in on that question by comparing people who ate the same foods – but at different times in the day.
眾所周知，吃飯晚更容易長(zhǎng)胖，但這是為什么呢？一項(xiàng)新研究對(duì)此給出了科學(xué)依據(jù)。該研究比較了在一天內(nèi)不同時(shí)段進(jìn)食相同食物的人。

“Does the time that we eat matter when everything else is kept consistent?” said first author Nina Vujovi?, a researcher in the division of sleep and circadian disorders at Boston’s Brigham and Women’s Hospital.
該研究論文第一作者、波士頓布里格姆婦女醫(yī)院睡眠和生物節(jié)律紊亂科研究員妮娜·武喬維奇提出：“當(dāng)其他因素都相同時(shí)，吃飯的時(shí)間有影響嗎？”

晚進(jìn)食會(huì)使感到更饑餓的可能性翻倍

The answer was yes – eating later in the day will double your odds of being hungrier, according to the study published in the journal Cell Metabolism.
答案是：是的。這篇發(fā)表在《細(xì)胞代謝》雜志上的研究論文顯示，吃飯晚會(huì)使感到更饑餓的可能性翻倍。

“We found that eating four hours later makes a significant difference for our hunger levels, the way we burn calories after we eat, and the way we store fat,” Vujovi? said. “Together, these changes may explain why late eating is associated with increased obesity risk reported by other studies and provide new biological insight into the underlying mechanisms.”
武喬維奇說(shuō)：“我們發(fā)現(xiàn)，晚4個(gè)小時(shí)進(jìn)食對(duì)饑餓程度、進(jìn)食后燃燒卡路里的方式以及儲(chǔ)存脂肪的方式都有顯著影響?？傊?，這些變化可能解釋其他研究發(fā)現(xiàn)的吃飯晚與肥胖風(fēng)險(xiǎn)增加的關(guān)聯(lián)，并為其中的潛在機(jī)制提供了新的生物學(xué)見解?！?/p>

The study provides support for the concept that circadian rhythm, which influences key physiologic functions such as body temperature and heart rate, affects how our bodies absorb fuel, researchers said.
研究人員稱，這項(xiàng)研究為以下觀點(diǎn)提供支持：生物節(jié)律影響體溫心率等關(guān)鍵生理功能，影響身體吸收能量的方式。

The study does show eating later results in “an increase in hunger, impacts hormones and also changes gene expression, especially in terms of fat metabolism with a tendency towards less fat breakdown and more fat deposition,” said Dr. Bhanu Prakash Kolla, a professor of psychiatry and psychology at the Mayo Clinic College of Medicine and a consultant to Mayo’s Center for Sleep Medicine and Division of Addiction Medicine.
巴努·普拉卡什·科拉博士稱，該研究確實(shí)表明，吃得晚會(huì)導(dǎo)致“饑餓感增加，影響激素水平，也會(huì)改變基因表達(dá)，特別是在脂肪代謝方面，會(huì)導(dǎo)致脂肪分解減少，脂肪沉積增多?！笨评敲穵W臨床醫(yī)學(xué)院精神病學(xué)和心理學(xué)教授、梅奧睡眠醫(yī)學(xué)中心和成癮醫(yī)學(xué)部顧問(wèn)。

The study was small – only 16 overweight or obese people – but carefully planned to eliminate other potential causes of weight gain, the authors said.
研究人員稱，這項(xiàng)研究規(guī)模較小，參與者只有16名超重或肥胖人士，但精細(xì)設(shè)計(jì)消除了導(dǎo)致體重增加的其他潛在原因。

“While there have been other studies investigating why late eating associates with an increased risk for obesity, this may be the most well controlled, including strictly controlling the amount, composition and timing of meals, physical activity, sleep, room temperature and light exposure,” said senior author Frank Scheer, director of the Medical Chronobiology Program in the Brigham’s Division of Sleep and Circadian Disorders.
布里格姆婦女醫(yī)院睡眠和生物節(jié)律紊亂科醫(yī)學(xué)生物鐘項(xiàng)目主任、研究主要作者弗蘭克·謝爾說(shuō)：“雖然有研究探索了吃飯晚與肥胖風(fēng)險(xiǎn)增加的關(guān)系，但我們的研究可能是變量控制最嚴(yán)格的。包括嚴(yán)格控制進(jìn)食量、餐食構(gòu)成和用餐時(shí)間、體力活動(dòng)、睡眠、室溫和光照?！?/p>

All participants were in good health, with no history of diabetes or shift work, which can affect circadian rhythm, and had regular physical activity. Each person in the study kept to a strict healthy sleep/wake schedule for about three weeks and were provided with prepared meals at fixed times for three days before the lab experiment began.
所有參與者健康狀況良好，沒(méi)有糖尿病史或值班工作史（這些因素可能會(huì)影響生物節(jié)律），并且會(huì)進(jìn)行規(guī)律的體育鍛煉。所有實(shí)驗(yàn)參與者都有嚴(yán)格的健康作息時(shí)間表，持續(xù)約三周，并在實(shí)驗(yàn)室實(shí)驗(yàn)開始前的三天內(nèi)，在固定的時(shí)間吃準(zhǔn)備好的餐食。

Participants were then randomized into two groups. One group ate calorie-controlled meals at 8 am, noon and 4 pm, while the other ate the same meals four hours later, at noon, 4 pm and 8 pm for the six days reported in the study. Measures of hunger and appetite were gathered 18 times each while tests for body fat, temperature and energy expenditures were gathered on three separate days.
參與者隨后被隨機(jī)分為兩組。在六天中，一組在上午8點(diǎn)、中午12點(diǎn)和下午4點(diǎn)吃控制熱量的飯菜，另一組晚四小時(shí)進(jìn)餐，分別在中午12點(diǎn)、下午4點(diǎn)和晚上8點(diǎn)吃同樣的飯菜。研究人員分別收集了18次兩組參與者的饑餓感和食欲的測(cè)量值，并在不同的三天里檢測(cè)他們的體脂、溫度和能量消耗。

After a break of a few weeks, the same participants reversed the procedure – those who had eaten earlier moved to the late eating group and vice versa, thus using each person as their own control.
休息幾周后，上述參與者重復(fù)相反的程序，那些吃飯較早的人改為較晚進(jìn)食，反之亦然，將每個(gè)人作為自己的對(duì)照。

Results showed that hunger pangs doubled for those on a night-eating regime. People who ate later in the day also reported a desire for starchy and salty foods, meat and, to a lesser extent, a desire for dairy foods and vegetables.
結(jié)果表明，晚進(jìn)食的人饑餓感增加了一倍。晚進(jìn)食的人稱，他們渴望吃含淀粉和咸味的食物、肉，相比之下，沒(méi)那么想吃乳制品和蔬菜。

晚進(jìn)食會(huì)影響食欲調(diào)節(jié)激素，從而增加食欲

By looking at the results of blood tests, researchers were able to see why: Levels of leptin, a hormone which tells us when we feel full, were decreased for late eaters versus early eaters. In comparison, levels of the hormone ghrelin, which spikes our appetite, rose.
通過(guò)查看血檢結(jié)果，研究人員發(fā)現(xiàn)了原因：與早進(jìn)食者相比，晚進(jìn)食者的瘦素水平降低，這是一種控制飽腹感的激素。相比之下，刺激食欲的激素胃促生長(zhǎng)素水平升高。

“What is new is that our results show that late eating causes an increase in the ratio of ghrelin and leptin averaged across the full 24-hour sleep/wake cycle,” Scheer said. In fact, the study found that the ratio of ghrelin to leptin rose by 34% when meals were eaten later in the day.
謝爾說(shuō)：“我們研究中的新發(fā)現(xiàn)是，晚進(jìn)食會(huì)導(dǎo)致整個(gè)生物節(jié)律中的胃促生長(zhǎng)素和瘦素比升高?！毖芯堪l(fā)現(xiàn)，晚進(jìn)餐時(shí)胃促生長(zhǎng)素和瘦素比升高了34%。

“These changes in appetite-regulating hormones fits well with the increase in hunger and appetite with late eating,” Scheer said.
謝爾說(shuō)：“這些食欲調(diào)節(jié)激素的變化與晚進(jìn)食導(dǎo)致的饑餓感和食欲的增強(qiáng)非常吻合?！?/p>

晚進(jìn)食會(huì)改變脂肪組織的基因表達(dá)，更利于脂肪儲(chǔ)存

When participants ate later in the day they also burned calories at a slower rate than when they ate at earlier times. Tests of their body fat found changes in genes that would impact how fat is burned or stored, the study found.
當(dāng)參與者吃飯較晚時(shí)，他們消耗的卡路里也比早吃飯時(shí)慢。研究發(fā)現(xiàn)，通過(guò)檢測(cè)參與者身體脂肪發(fā)現(xiàn)，基因的變化會(huì)影響脂肪的燃燒或儲(chǔ)存方式。

“These changes in gene expression would support the growth of fat tissue by formation of more fat cells, as well as by increased fat storage,” Scheer said.
謝爾說(shuō)：“基因表達(dá)發(fā)生變化，將通過(guò)形成更多的脂肪細(xì)胞以及增加脂肪儲(chǔ)存來(lái)支持脂肪組織的生長(zhǎng)?！?br>

來(lái)源：CNN，梅斯醫(yī)學(xué)
編輯：董靜