咖啡成為越來越多現(xiàn)代人生活必不可少的一部分。一杯香濃的咖啡，能給快節(jié)奏高壓力的學(xué)習(xí)工作生活注入一股能量。當(dāng)然，咖啡不光能使人精神抖擻，也有它的“副作用”，就是能讓人“便意盎然”。

Like opening the blinds and stepping into the shower, a cup of coffee gets people moving in the morning — in more ways than one. This satisfying brew revs energy levels with a dose of caffeine and, for many people, quickly and reliably jump-starts gut activity and an urgent need to poop.

就像打開百葉窗和沖淋浴一樣，一杯咖啡能讓人在早上振作起來——多方面的振作。這種令人滿足的飲品通過咖啡因來提升人的能量水平，而且對許多人來說，它能迅速可靠地啟動腸道活動和排便的迫切需求。

But given coffee’s popularity, it’s surprising that we know so little about how it affects the gastrointestinal tract, said Dr. Robert Martindale, a professor of surgery and the medical director for hospital nutrition services at Oregon Health and Science University.

但是，俄勒岡健康與科學(xué)大學(xué)外科教授、醫(yī)院營養(yǎng)服務(wù)醫(yī)療主任羅伯特·馬丁代爾說，令人意外的是，咖啡這么受歡迎，但我們對它的胃腸道影響其實(shí)知之甚少。

Some studies on the topic — which tend to be small, old and limited — have suggested that it’s probably not the caffeine that triggers the urge to go. One paper published in 1998, for instance, found that decaffeinated coffee had a similar stimulatory effect on the colon as caffeinated coffee, whereas a cup of hot water did not.

關(guān)于這個問題的研究往往是小型、陳舊和有限的，但其中一些表明，觸發(fā)這種沖動的可能不是咖啡因。例如，1998年發(fā)表的一篇論文發(fā)現(xiàn)，低因咖啡和含咖啡因的咖啡對結(jié)腸有類似刺激作用，而熱水則沒有。

Coffee is a complex beverage containing more than 1,000 chemical compounds, many of which have antioxidant and anti-inflammatory properties. And determining how they affect the intestines is challenging.

咖啡是一種復(fù)雜的飲料，含有1000多種化合物，其中許多具有抗氧化和消炎的特性。確定它們?nèi)绾斡绊懩c道是很困難的。

One thing we do know is that coffee doesn’t affect everyone the same way. In one study published in 1990 in the journal Gut, 92 young adults filled out a questionnaire about how coffee affected their bowel habits; just 29 percent of the respondents said it “induced a desire to defecate,” and most of them — 63 percent — were female. (Though Dr. Martindale said that the percentage of people who have a bowel response after drinking coffee is likely much higher in the general population — he estimated that around 60 percent of his patients do — and he hasn’t noticed any differences between men and women.)

我們知道，咖啡對每個人的影響并不相同。1990年發(fā)表在《腸道》雜志上的一項(xiàng)研究中，92名年輕人填寫了一份關(guān)于咖啡如何影響排便習(xí)慣的問卷。只有29%的受訪者表示它能“誘發(fā)排便欲”，其中多數(shù)（63%）是女性。（但馬丁代爾說，在一般人群中，喝完咖啡后出現(xiàn)排便反應(yīng)者的比例可能要高得多——他估計(jì)他的病人中大約有60%是這樣的——而且他沒有發(fā)現(xiàn)男性和女性之間有任何差異。）

We also know that a gut response to coffee can happen fast. In the same study, some volunteers agreed to have a pressure-sensing probe inserted into their colon to measure intestinal muscle contractions before and after drinking a cup of Joe. Among those who said that coffee usually stimulated a bowel movement, the probe showed a significant increase in pressure within four minutes of drinking coffee, while the so-called nonresponders had no change in colon activity.

我們也知道，腸道對咖啡的反應(yīng)會很快發(fā)生。在同一項(xiàng)研究中，一些志愿者同意在結(jié)腸中插入一個壓力感應(yīng)探針，以測量喝咖啡前后腸道肌肉的收縮情況。在那些說咖啡通常會刺激排便的人當(dāng)中，在喝咖啡后四分鐘內(nèi)，探針顯示的壓力會顯著增加；而自稱無反應(yīng)者的結(jié)腸活動沒有變化。

That drinking a cup of coffee can stimulate the opposite end of the gastrointestinal tract within minutes means “it’s probably going through the gut-brain axis,” Dr. Martindale said. That is, the arrival of coffee in the stomach sends a message to the brain, which then “stimulates the colon to say, ‘Well, we’d better empty out, because things are coming downstream,’” he explained. The coffee itself would move through the intestines much more slowly, likely taking at least an hour to traverse the long path from the stomach through the small intestine and to the colon.

喝一杯咖啡可以在幾分鐘內(nèi)就刺激胃腸道的另一端，這意味著“它可能會通過腸道-大腦軸，”馬丁代爾說。也就是說，咖啡到達(dá)胃部后會向大腦發(fā)送信息，然后“刺激結(jié)腸說，‘好吧，我們最好清空所有東西，因?yàn)橛袞|西要下來了，’”他解釋說?？Х缺旧硗ㄟ^腸道的速度會慢得多，可能需要至少一個小時才能走完從胃通過小腸到達(dá)結(jié)腸這段長長的路程。

This communication between the stomach, brain and colon, called the gastrocolic reflex, is a normal response to eating. But coffee seems to have an outsize effect; one study published in 1998 found that eight ounces of coffee stimulated colonic contractions similar to those induced by a 1,000-calorie meal. Researchers have hypothesized that coffee’s gut-brain messaging is likely caused by one or more of coffee’s many chemicals, and perhaps mediated by some of our own hormones that play important roles in the digestive process, like gastrin or cholecystokinin — both of which can spike after coffee drinking.

胃、大腦和結(jié)腸之間的這種交流被稱為胃結(jié)腸反射，是對進(jìn)食的正常反應(yīng)。但咖啡似乎對其有巨大的影響；1998年發(fā)表的一項(xiàng)研究發(fā)現(xiàn)，約230毫升的咖啡刺激結(jié)腸收縮，類似于1000卡路里的膳食所引起的收縮。研究人員推測，咖啡的腸道-大腦信息傳遞可能是由咖啡多種化學(xué)物質(zhì)中的一種或多種引起的，也可能是由我們自身一些在消化過程中扮演重要角色的激素介導(dǎo)的，比如胃泌素或膽囊收縮素——這兩種物質(zhì)在喝咖啡后都會激增。

While the mechanism remains murky, coffee’s effects on the gut may be helpful for some people, including those recovering from certain types of surgery. Impaired bowel function is common after abdominal surgeries, for instance, which can lead to bloating, pain and an inability to pass gas or tolerate food. A 2020 analysis combined the results of seven clinical trials and found that drinking coffee allowed patients who had undergone colorectal or gynecological surgery to tolerate solid foods an average of 10 and 31 hours sooner, respectively. Coffee also reduced the time to their first bowel movement, by an average of 15 to 18 hours.

雖然機(jī)制仍然很模糊，但咖啡對腸道的影響可能對一些人有幫助，包括從某些類型的手術(shù)中恢復(fù)的人。例如，腹部手術(shù)后腸道功能受損很常見，可能會導(dǎo)致腹脹、疼痛、無法排氣或無法耐受食物。2020年的一項(xiàng)分析綜合了七項(xiàng)臨床試驗(yàn)的結(jié)果，發(fā)現(xiàn)喝咖啡可以讓接受結(jié)腸、直腸手術(shù)和婦科手術(shù)的患者固體食物耐受分別平均提前10小時和31小時?？Х冗€減少了他們術(shù)后第一次排便所需的時間，平均為15到18個小時。

Sonya Angelone, a registered dietitian and spokeswoman for the Academy of Nutrition and Dietetics, cautioned against relying too much on coffee to stay regular. If someone is constipated, “it is not because they have a deficiency of coffee,” she said. Ms. Angelone recommends eating more fruits and vegetables, which are high in fiber, as well as increasing fluid intake and physical activity to address constipation. “What I find for a lot of people is they don’t start off with a fiber punch in the morning,” she said. Brewed coffee contains a small amount of fiber, about one gram per eight-ounce cup.

注冊營養(yǎng)師、美國營養(yǎng)與飲食學(xué)會的發(fā)言人桑婭·安吉羅警告說，不要過度依賴咖啡來維持排便規(guī)律。她說，如果有人便秘，“并不是因?yàn)樗麄內(nèi)狈Х?。”安吉羅建議多吃富含纖維的水果和蔬菜，并增加液體攝入量和體育活動來解決便秘問題。她說：“我發(fā)現(xiàn)，很多人早上起床時都不會攝入膳食纖維?！敝蠛玫目Х戎泻猩倭坷w維，大約每230毫升咖啡中含有1克纖維。

Some people find that coffee causes an upset stomach and loose stools, as well as side effects linked to excess caffeine, like insomnia, anxiousness, heart palpitations and headache, Ms. Angelone added. The Food and Drug Administration says that it’s safe for most people to drink 400 milligrams of caffeine — the amount in about four or five cups of coffee — per day. Though keep in mind that people metabolize caffeine differently, so this threshold can vary from person to person. “Coffee is one of those things, unlike other foods, that if it bothers you, you know it,” Ms. Angelone said.

安吉羅還說，有些人發(fā)現(xiàn)咖啡會導(dǎo)致胃部不適和軟便；還會產(chǎn)生與咖啡因過量相關(guān)的副作用，比如失眠、焦慮、心悸和頭痛。美國食品和藥物管理局表示，對大多數(shù)人來說，每天飲用400毫克的咖啡因是安全的——相當(dāng)于四到五杯咖啡中的咖啡因含量。不過要記住，每個人對咖啡因的代謝情況是不同的，所以這個閾值因人而異?！翱Х炔幌衿渌澄?，如果它讓你感到不舒服，你就能感受到，”安吉羅說。

知道你有沒有喝咖啡的習(xí)慣，咖啡在現(xiàn)代社會已經(jīng)成為了許多人生活必不可少的一部分。一天的工作生活，好像都需要一杯香濃的咖啡才能喚醒。當(dāng)然，咖啡不光能使人精神抖擻，也有它的“副作用”，就是能讓人“便意盎然”。今天的文章會告訴我們，咖啡為什么會讓人產(chǎn)生排便感。

詞匯：

rev v. 使加速；增加

a dose of? ? ? ? ? ? ? ? ? ? 一劑（藥）

jump-start? ? ? ? ? ? ? ? ? v. 啟動，發(fā)動=

given? ? ? ? ? ? ? ? ? ? ? ? ? prep. 考慮到，如果

gastrointestinal? ? ? ? 腸胃的

~ tract? ? ? ? ? ? ? ? ? ? ? ? 胃腸道

urge? ? ? ? ? ? ? ? ? ? ? ? ? ? ? n. 強(qiáng)烈的欲望，沖動

decaffeinated? ? ? ? ? ? v. 脫咖啡因的，無咖啡因的

antioxidant? ? ? ? ? ? ? ? ? n. 抗氧化劑

anti-inflammatory? ? ? a. 抗炎的

intestine? ? ? ? ? ? ? ? ? ? ? ? n. （脊椎動物的）腸

bowel? ? ? ? ? ? ? ? ? ? ? ? ? ? n. 腸，腸道

defecate? ? ? ? ? ? ? ? ? ? ? ? v. 澄清，排便

colon? ? ? ? ? ? ? ? ? ? ? ? ? ? ? n. 結(jié)腸

axis? ? ? ? ? ? ? ? ? ? ? ? ? ? ? n. 軸，軸線，對稱軸

traverse? ? ? ? ? ? ? ? ? ? ? v. 橫穿，穿過

gastrocolic reflex? ? ? ? 胃結(jié)腸反射

murky? ? ? ? ? ? ? ? ? ? ? ? a. （液體）渾濁的；復(fù)雜的，難以理解的

impaired? ? ? ? ? ? ? ? ? a. 受損的，出毛病的

bloat? ? ? ? ? ? ? ? ? ? ? ? ? v. 使膨脹，腫脹，脹氣

gynecological? ? ? ? ? a. 婦科的，婦產(chǎn)科醫(yī)學(xué)的

constipate? ? ? ? ? ? ? ? v. 便秘

intake? ? ? ? ? ? ? ? ? ? ? ? n. （食物等）攝取量

upset stomach? ? ? ? ? ? 肚子疼，腸胃不適

loose stool? ? ? ? ? ? ? ? ? 軟便，便溏

excess? ? ? ? ? ? ? ? ? ? ? ? ? 超過，過量

insomnia? ? ? ? ? ? ? ? ? ? ? n. 失眠癥

palpitation? ? ? ? ? ? ? ? ? n. 心悸，心慌

metabolize? ? ? ? ? ? ? ? ? v. 新陳代謝

threshold? ? ? ? ? ? ? ? ? ? n. 門檻，閾值

https://www.nytimes.com/2021/11/30/well/eat/why-does-coffee-make-you-poop.html?searchResultPosition=1