導讀文章探討了咖啡對人體健康的多面性影響。咖啡是全球廣泛飲用的飲品,每天約有20億杯被消費。研究表明,適量飲用咖啡對健康無害,甚至可能有益。咖啡中的咖啡醇、咖啡豆醇、咖啡因和咖啡綠原酸等成分,能減少炎症和氧化引起的細胞損傷,還可能抑制腫瘤生長和致癌物質的形成,有助於預防癌症。有研究發現,每天飲用三到四杯咖啡的絕經後婦女患乳腺癌機率較低,每天飲用三杯或更多咖啡的人患肝癌風險也有所降低。此外,咖啡因可能降低患阿爾茨海默病、帕金森病和抑鬱症等疾病的風險,但相關研究結果並不一致,這可能與咖啡的多樣性有關。不過,過量飲用咖啡會導致頭痛、緊張、易怒等不良後果,還可能加重心臟病等慢性健康問題。而且,咖啡中加入的牛奶、糖等物質若長期過量攝入也會對健康造成傷害。一項針對46000多名成年人的研究顯示,每天飲用1到3杯純黑咖啡的參與者在未來十年內死亡的可能性比不喝咖啡的人低15%左右,但如果加入過多奶油或糖,這種益處就會消失。因此,適量飲用咖啡並選擇純黑咖啡,可最大限度發揮其健康益處。How much coffee is too much?喝多少咖啡才算太多?Studies suggest moderate consumption is harmless, and may event be beneficial研究表明,適度消費是無害的,甚至可能是有益的Humanity drinks around 2bn cups of coffee every day. The good news for those who contribute to that figure is that regularly consuming moderate amounts does not appear to be harmful. There may even be health benefits. Experiments conducted in vitro and in animals have long shown that some components of coffee, including cafestol, kahweol, caffeine and chlorogenic acids, can reduce inflammation as well as cell damage caused by a chemical process known as oxidation.人類每天大約飲用20億杯咖啡。對於那些為這一數字做出貢獻的人來說,好消息是,定期適量飲用咖啡似乎並無害處,甚至可能有益健康。早在多年前,體外實驗和動物實驗就已表明,咖啡中的一些成分,包括咖啡醇(cafestol)、咖啡豆醇(kahweol)、咖啡因和咖啡綠原酸,能夠減少炎症以及由氧化這一化學過程引起的細胞損傷。When a team led by Marzieh Moeenfard of the University of Porto looked more closely, they found that the potential benefits ran deeper. She reported in the Journal of Cellular Biochemistry in 2016 that cafestol and kahweol (which tend to be more prevalent in unfiltered than in filtered coffee) arrested tumour growth by making it less likely that new blood vessels would form around tumour cells, and that chlorogenic acids inhibited the formation of carcinogens within the body. This suggested coffee might be good for fending off cancer.當波爾圖大學的Marzieh Moeenfard領導的研究小組更深入地研究時,他們發現潛在的好處遠不止於此。她在2016年發表於《細胞生物化學雜誌》上的一篇報告中指出,咖啡醇和咖啡豆醇(在未過濾咖啡中比在過濾咖啡中更為常見)通過降低腫瘤細胞周圍新生血管形成的機率來抑制腫瘤生長,而咖啡綠原酸則抑制了體內致癌物質的形成。這表明咖啡或許有助於預防癌症。One follow-up study led by Jin-Kyoung Oh of the Karolinska Institute in Stockholm reported that post-menopausal women who claimed to drink three or four cups of coffee per day were significantly less likely to develop breast cancer than women who said they drank up to two cups. Similar work in Japan suggested that those who said they drank three or more cups every day had a reduced risk of developing liver cancer.斯德哥爾摩卡羅林斯卡研究所的Jin-Kyoung Oh領導的一項後續研究表明,聲稱每天飲用三到四杯咖啡的絕經後婦女患乳腺癌的機率,明顯低於那些聲稱每天飲用不超過兩杯的婦女。類似的研究在日本表明,聲稱每天飲用三杯或更多咖啡的人患肝癌的風險有所降低。Because caffeine is a stimulant that improves mood and combats tiredness, its presence in coffee has prompted some to test whether it reduces the risk of a person developing psychiatric and neurological diseases like Alzheimer’s, Parkinson’s and depression. Some have found beneficial effects. For example, Hong Chien-Tai of Taipei Medical University reported in 2020 that in patients with Parkinson’s who consumed caffeine regularly, their disease progressed more slowly than in those who abstained.由於咖啡因是一種能改善情緒、對抗疲勞的興奮劑,它存在於咖啡中促使一些人去測試其是否能降低人們患阿爾茨海默病、帕金森病和抑鬱症等精神和神經疾病的風險。一些研究發現了有益的效果。例如,台北醫科大學的洪建泰(Hong Chien-Tai)在2020年報告稱,在定期攝入咖啡因的帕金森病患者中,其病情進展比那些戒掉咖啡因的人更緩慢。Other findings, whether on cancer or mental health, have yielded mixed results. The uncertainty may well come down to the multitudes that coffee contains. Beans are sourced from different species, roasted in different fashions and served up in a variety of drinks of different sizes and strengths. Still, moderate consumption seems, at worst, harmless.其他研究,無論是關於癌症還是心理健康,結果都褒貶不一。這種不確定性很可能源於咖啡的多樣性。咖啡豆來自不同的品種,烘焙方式不同,並且被製成各種不同大小和濃度的飲品。儘管如此,適量飲用咖啡似乎最多也無害。Overindulgence has clearer-cut consequences. Ingesting more than 400 milligrams of caffeine daily (an espresso contains around 60) has been found to lead to headaches, nervousness, irritability, muscle tremors and insomnia. It is also associated with mental-health conditions such as anxiety, and can make chronic health problems, like heart disease, worse by increasing blood pressure. The effects of overdosing on coffee’s other active ingredients are unclear.過度飲用咖啡的後果則更加明確。每天攝入超過400毫克的咖啡因(一杯濃縮咖啡大約含有60毫克)會導致頭痛、緊張、易怒、肌肉震顫和失眠。它還與焦慮等精神健康問題有關,並且可以通過增加血壓使慢性健康問題(如心臟病)變得更糟。過量攝入咖啡中其他活性成分的影響尚不清楚。But these are not the only risks associated with drinking coffee. Many lace their cup with additives like milk, sugar, cream and syrup, chronic overconsumption of which can also cause harm. A study of over 46,000 adults published in the Journal of Nutrition in May is suggestive. The results showed that participants who drank between one and three cups of coffee per day were roughly 15 percent less likely to die during the next decade than those who consumed none. That said, the benefit vanished if they stirred more than around a teaspoon of cream or half a teaspoon of sugar into their drink.但這些並非與飲用咖啡相關的唯一風險。許多人會在咖啡中加入牛奶、糖、奶油和糖漿等加入劑,這些加入劑的長期過量攝入也會造成傷害。5月發表在《營養學雜誌》上的一項針對46000多名成年人的研究具有一定的啟示性。結果顯示,每天飲用1到3杯咖啡的參與者在未來十年內死亡的可能性比那些不喝咖啡的人大約低15%。不過,如果他們在咖啡中加入超過大約一茶匙的奶油或半茶匙的糖,這種益處就會消失。To maximise the benefits, therefore, don’t overdo the cups and take it as black—and as bitter—as you like.因此,為了最大限度地發揮咖啡的益處,不要過度飲用,並且按照你喜歡的方式,儘可能選擇純黑咖啡——越苦越好。 (Chris的外刊閱讀筆記)