Study Says Excess 过量饮用咖啡会导致早逝？言之过早

Study Says Excess Coffee May Be Linked To Early Death. Should We Believe It?

过量饮用咖啡会导致早逝？言之过早

Steel yourself for the results of a new study that’s making headlines: Those of us under 55 who drink a lot of coffee – more than four cups per day – may be at greater risk of an early death. And not death from heart problems, but death from all causes. The study, from Mayo Clinic Proceedings, followed people for almost two decades, and found that in both sexes, younger people were more likely to die of anything than people who drank less. Though it may sound bleak, the study really just adds to the mishmosh of coffee studies all pointing at different outcomes. And good news remains –many earlier studies have found that heavy coffee consumption is linked to reduced mortality. So the logical advice is still to enjoy your daily ritual if it seems to work for you.

最近，有一项新的研究结论引起了媒体的广泛报道。在看这个结论之前，请先做好思想准备：研究表明，每天过量饮用咖啡，具体来说是每天喝超过4杯咖啡，将会导致年龄55岁以下人群的早逝风险增加，而且死亡原因并非是心脏问题，而是由各种因素导致。这份刊登在《梅奥诊所学报》（Mayo Clinic Proceedings）上的报告称，研究者们对受访者进行了近20年的持续跟踪与分析，结果发现，在较年轻人群中（无论男女），相比那些较少饮用咖啡的人，过量饮用咖啡者的死亡风险要更高。这项研究的结论听起来让人沮丧，但是此前有关咖啡的众多研究得出了各不相同的结论，这一报告使结论更加纷杂。而且，好消息仍然存在，许多早期的研究表明，大量饮用咖啡与减小死亡率有关。在这样的情况下，合乎逻辑的建议是，如果你觉得饮用咖啡对你有好处，你仍然可以每天享用。

But here’s what the new study found. The team tracked almost 44, 000 participants for 17 years, noting how many people died, and of what cause. Lifestyle factors like coffee consumption, diet, exercise, smoking, and weight were taken noted and potential confounders controlled for. It turned out that 2, 500 people died during the study period, with men making up over 87% of those deaths.

但我们还是要来看看这项新的研究所得出的结论。这个研究团队花了17年的时间，跟踪了近44,000位受访者，并对他们的死亡率和死亡原因加以分析。研究人员跟踪记录了这些受访者的生活方式与习惯，其中包括咖啡饮用量、饮食、运动、吸烟以及体重等，并与潜在的干扰因素相对照。研究结果发现，在整个调查期间共有2,500人死亡，死者中男性的比例超过87%。

The headline-worthy results: People under 55 who drank more than 28 cups per week were more like to die of almost any cause than people who drank less. Women were twice as likely to die from any cause and men were 56% more likely, compared to people who drank less. Even controlling for cigarette smoking, which is generally the big confounder in coffee studies, did not totally eliminate the link.

最终的结论令人震惊，足以登上报纸的头条。这项研究发现，55岁以下人群中，比起较少饮用咖啡的人来说，每周饮用咖啡超过28杯的人的死亡率上升，死亡原因也多种多样。研究还发现，如果每周饮用28杯咖啡，55岁以下女性因任何因素导致的死亡风险增加了一倍，而男性则增加了56%。吸烟通常被认为是咖啡健康影响研究中的一个很大干扰因素，但即便与“吸烟”这项因素相对照，也并没有完全消除过量饮用咖啡与死亡率上升之间存在的关联性。

Before you panic and switch to tea, keep in mind some drawbacks of the study. One problem is that no one really knows what mechanism/s could explain the coffee-death link. Some are candidates, however: There’s coffee’s ability to boost epinephrine (adrenalin) levels in the body, its inhibition of insulin function (though this is controversial), and the fact that it may raise blood pressure and homocysteine levels, which are both known to increase heart risk (though since heart disease was not increased in the study, these seem less

likely).

在你惊慌失措并想转向茶叶之前，先想想这项研究存在的某些缺陷和不足。其中的一个问题是，没有人真正清楚，究竟是什么机理导致了过量饮用咖啡与死亡率升高之间的关联。不过，有一些因素可供考虑：比如咖啡能够提升体内的肾上腺素水平，这会抑制体内胰岛素发挥作用（这一点医学界目前尚存争议），而且咖啡因还会提高血压和体内的同型半胱氨酸水平，这都是已知的导致心脏病风险上升的原因（但是在这项研究中，由心脏病导致的死亡率并没有提高，因此这些因素似乎不太可能是真正的根源）。

Another big caveat is the age issue – the coffee-death relationship was only true for people under 55 –and the reason behind this is somewhat of a mystery. It could be that people who are dying this young are already predisposed to fatal health problems in various ways, although this is somewhat speculative. Study author Chip Lavie points out that heavy coffee drinkers differ in a number of ways from less avid consumers, so there may be other, as-yet-undiscovered things going on. The authors suggest that since heart disease wasn’t increased among heavy coffee drinkers, but rather death from all causes, cancer may be a culprit. “Certainly, one would think that the main non-CV cause of death would be cancer, but we did not specifically assess this. And with cancer, one would really want to know cause-specific as opposed to cancer in general – we will probably try to assess this, although this is not quite as easy as one may think.”

另一个值得注意的是年龄问题。过量饮用咖啡与死亡率升高之间的关联似乎仅发生在年龄55岁以下的人群中，而其背后的原因在某种程度上也是一个谜。这些英年早逝的人或许在此前就因为各种原因存在致命的健康问题，虽然这也只是一种猜测。研究者奇普?李维（Chip Lavie）指出，过量饮用咖啡的人与不那么爱喝咖啡的人，在许多方面都存在着差异，因此，这背后或许有别的未被发现的因素在起作用。研究者称，在过量饮用咖啡的人群中，心脏病的发病比例并未上升，而在各种死因之中，癌症可能是首要原因。“很明显，人们会据此认为，癌症是

非心血管疾病死亡的罪魁祸首，但是我们并没有针对此做过专门的评估。对于癌症，人们也总是想知道特定原因的死亡率相对于癌症总体死亡率的情况。我们也许会尝试去做这样的评估，但这却并不像人们想得那么简单。”

If you’re wondering about how decaf might affect things, that answer too is unclear. The study controlled for decaf (although most people didn’t drink it anyway), meaning that only caffeinated coffee was included in the correlation with mortality. However, Lavie points out that since heart disease deaths were not raised among the heavy coffee drinkers, one might expect the same link to be true for decaf as well. “When this questionnaire was administered 25-30 years ago, ”he says, “there was not much use of decaf coffee, so whether this relates with regular vs. all coffees would be guessing. If the mortality was due to cardiovascular, we would speculate that it may not apply to decaf, but we saw no increase in cardiovascular mortality in any of the groups at any of the doses.”

或许你也想知道，喝脱咖啡因咖啡会有什么影响，然而，关于这一点的答案也是模棱两可的。这是一项脱咖啡因咖啡对照研究（虽然大部分人不会喝这种咖啡），这意味着在研究与死亡率之间的相互关系时，仅仅将含咖啡因咖啡纳入考量。然而，李维指出，由于在过量饮用咖啡的人群中，死于心脏病的比率并没有上升，因此，人们也许会想知道，对于脱咖啡因咖啡是否也会是同样的结果。“这份问卷调查是在25-30年前进行的，”李维说。“当时脱咖啡因咖啡还不普及，所以究竟是所有咖啡品种都与心脏病之间有着这样的关联关系，还是仅仅是普通咖啡与之有关联，我们不得而知。如果死亡率与心血管疾病有关，那么我们就可以猜测这种关联性可能不适用于脱咖啡因咖啡，但我们发现，在任何一组研究人群中，不论饮用量大小，我们并没有看到心脑血管疾病所造成的死亡率出现上升。”Also keep in mind, the current study only points to a correlation, not cause-and-effect. And it only measured coffee consumption at one time-point, not many throughout the years. There could be a lot of other things at play. “It is impossible to know if this association is causal or just an association, ”says Lavie, “so one does not want to over-state or over-hype the dangers of

drinking more than 28 cups per week, although I personally will make an effort to keep my cups at 3 or less most of the time.”

另外还要注意的是，目前这个研究仅仅是指出了过量饮用咖啡与死亡率升高之间存在着相关性，而不是说这两者之间存在因果关系。而且，该研究仅衡量了某一个时间点上饮用咖啡的量，而非常年饮用量，或许这其中会有很多其他的因素在发挥作用。“不可能确定这是一种因果关系或仅仅只是一种关联关系，”李维表示，“所以，无需过分夸张或是大肆宣传每周饮用超过28杯咖啡所带来的风险。但从我个人来说，我会在大部分时间内，把每日的咖啡饮用量限定在3杯或以内。”

But perhaps most uplifting of all is to remember that findings from a number of earlier studies contradict the new one and suggest that coffee is actually, at least on average, good for us. In fact, one recent study in The New England Journal of Medicine, following some 400, 000 people, suggested that drinking up to six cups per day is actually linked to reduced mortality from all causes –10% for men and 15% for women. The results were true whether the people drank caffeinated coffee or decaf. Given the high levels of antioxidants in coffee, there may be some logical explanations for its connection to enhanced health and longer lifespan. The authors of that study write, “Our results provide reassurance with respect to the concern that coffee drinking might adversely affect health.”

但最令人感到安慰的或许是，此前一系列有关咖啡对健康影响的研究所得出的结论与这一新结论相左，以前的结论表明，至少从一般情况来说，咖啡对健康是有益的。《新英格兰医学杂志》（The New England Journal of Medicine）最近发表了一项研究报告，在跟踪了近40万受访者之后得出结论称，每天最多喝6杯咖啡与各种原因死亡率的下降间存在联系，其中男性的死亡率下降了10%，女性的死亡率下降15%，无论受访者饮用的是含咖啡因咖啡还是脱咖啡因咖啡，结果都是如此。考虑到咖啡中含有大量的抗氧化剂，或许这是咖啡能改善健康和延年

益寿的一个合乎逻辑的解释。这项研究的作者们写道：“我们的研究结论可以令那些担心咖啡会损害健康的人安心”。

Because of individual differences, genetics, and the myriad lifestyle choices we make every day, there are sure to be interactions going on that make the connection much more complicated than “coffee=death”or “coffee=longevity.” Depending on all these factors, for some, coffee may be good, for others not so. So while we’re waiting for the research to give us a clearer picture, talk to your doc, or go with your gut and do what you feel works best for you.

我们每个人的个体、基因以及日常的生活方式都各有不同，其中肯定会有一些相互作用，使得情况变得更为复杂，所以我们不能简单地认为“咖啡=死亡”或“咖啡=长寿”。正是由于所有这些不同的因素，对有些人来说，喝咖啡或许能够有益健康，而对其他人来说却并非如此。因此，在等待研究者给我们一个更为明确的结论之前，请去咨询医生，或者就大胆一点，觉得怎样对你最好就怎样做。