Some people choose to drink a cup of coffee to start a new day. Others might notice that the drink tames their hunger， too. Many people on social media are increasingly drinking their favorite pick-me-up to shed pounds. But studies are only beginning to explain how caffeine and other compounds in coffee might affect weight.

一些人選擇喝一杯咖啡來開啟新的一天。有人可能會注意到這種飲料也能讓他們不感到饑餓。社交媒體上有許多人越發(fā)頻繁喝他們最喜歡的提神飲料來減肥。但有關(guān)咖啡中的咖啡因和其他化合物如何影響體重的研究卻并不多。

Coffee and other caffeine products have been rumored to be a quick， easy weight-loss food. The reason is partly linked to coffee’s ability to get the digestive system moving. The caffeine in coffee can ramp up muscle contractions in the colon that stimulate bowel movements. That means the digestive" "system clears its contents a little quicker than usual. Caffeine is also a diuretic， meaning it increases urine production， and peeing more causes a loss of water weight. These combined effects on digestion and water weight happen quickly after consuming coffee but are short-lived—they don’t cause permanent weight loss. Consuming coffee over longer periods of time， however， seems to bring on different effects.

有傳言說咖啡和其他咖啡因產(chǎn)品是一種快速、簡單的減肥食品。其部分原因與咖啡活絡(luò)消化系統(tǒng)的能力有關(guān)?？Х戎械目Х纫蚩梢约涌旖Y(jié)腸肌肉的收縮，從而刺激排便。這意味著消化系統(tǒng)可以比平時更快地消化食物。咖啡因也是一種利尿劑，這意味著它會使尿液增多，而頻繁地排尿會讓身體的水分減少。飲用咖啡之后這些對消化和水重的綜合影響會立竿見影，但持續(xù)時間卻不長，咖啡并不會長久性地減掉體重。然而，長時間飲用咖啡似乎會帶來不同的效果。

Caffeine， the primary bioactive compound in coffee， appears to be one of the main drivers of the reduced weight gain. The compound is known to stimulate diet-induced thermogenesis—the energy used to digest， absorb and store nutrients from food. On average， people spend about 10 percent of their total energy expenditure processing food. Studies have shown that caffeine can increase that amount by raising a person’s metabolic rate. A higher metabolic rate causes the body to use more energy at rest. The digestive process speeds up， causing organs in the gut to use slightly more energy and burn more calories. Overall， this energy increase is small， however， coffee drinkers might burn 80 to 150 more calories per day， according to one short-term study.

咖啡中的主要活性成分咖啡因似乎是防止體重增加的一種重要物質(zhì)。眾所周知，咖啡因能夠刺激飲食誘導(dǎo)的產(chǎn)熱，即用于消化、吸收和儲存食物營養(yǎng)的能量。通常來說，人們在消化食物時需要消耗的能量約為總能量的10%。研究顯示，咖啡因可以通過提高新陳代謝率來增加這一能量消耗。更高的新陳代謝率會讓在靜息狀態(tài)下的身體消耗更多能量。消化過程加快，可以讓腸道器官消耗稍微多一點的能量，燃燒更多卡路里。但總的來說，能量增幅很小，一項短期研究顯示，喝咖啡的人每天可能多燃燒80到150卡路里。

Drinking coffee regularly doesn’t lead to significant weight loss， but it may prevent weight gain—although modestly. The average person typically gains weight as they get older—about a pound per year through middle age—but coffee drinkers seem to experience less age-related weight gain. A study followed the coffee habits of more than 150，000 participants and found that drinking unsweetened coffee was associated with a modest reduction in weight gain over four years after adjusting for other lifestyle variables. With each additional cup， the coffee drinkers gained about a quarter of a pound less than their peers. Most people probably won’t feel such a small difference in weight， though.

定期喝咖啡并不會使體重顯著減輕，但可能會防止體重增加，盡管收效甚微。一般來說，年紀越大，人的體重也會增加，中年人每年大約增加一磅。但喝咖啡的人的體重似乎較少隨年齡增長而增加。一項研究跟蹤調(diào)查了超15萬名受試者喝咖啡的習(xí)慣，發(fā)現(xiàn)在調(diào)整了其他與生活方式有關(guān)的變量后，四年內(nèi)喝無糖咖啡與體重增加幅度的降低有一定關(guān)聯(lián)。每多喝一杯咖啡，他們增加的體重要比同齡人少約0.25磅。不過，大多數(shù)人可能感受不到如此微小的體重變化。

Word Bank

tame /te?m/ v. 馴化；使易于控制

be rumored 謠傳；傳說

ramp up 使增加；增加