Many of us try, but often fail, to get eight hours’sleep each night. This is widely assumed to be the ideal amount -but some experts now say it’s too much, and may actually beunhealthy。

　　我们中很多人都想每晚睡够8个小时，只是经常做不到。8小时是广为赞同的最理想的睡眠时间，但有些专家表示睡8小时或许太久，并且有可能对身体有害。

　　We all know that getting too little sleep is bad. Youfeel tired, you may be irritable, and it can contribute to obesity,high blood pressure, diabetes, and heart disease, doctors say. Buttoo much sleep? You don’t often hear people complaining aboutit。

　　我们都知道睡得太少对身体不好。你会疲劳不堪，急躁易怒，并且医生表示这也可能导致肥胖，高血压，糖尿病和心脏疾病。但是睡太多好吗？你并不经常听到有人抱怨自己睡太多。

　　However, research carried out over the past 10 yearsappears to show that adults who usually sleep for less than sixhours or more than eight, are at risk of dying earlier than thosesleep for between six and eight hours。

　　但是，过去10年中进行的实验似乎证明睡眠经常少于6小时或多于8小时的成年人有可能比睡眠时间在6-8小时之间的人死亡得早。

　　To put it more scientifically, there is a gradualincrease in mortality risk for those who fall outside thesix-to-eight-hour band。

　　换种更科学的说法就是，睡眠不在6-8小时内的人群死亡率正不断上升。

　　Prof Franco Cappuccio, professor at the University ofWarwick, has analysed 16 studies, in which overall more than amillion people were asked about their sleeping habits and thenfollowed up over time。

　　英国华威大学的教授佛朗哥·卡普里奥分析了16个研究，在这些研究中有百多万人报告了自己的睡眠习惯，团队也一直在追踪调查。

　　His analysis showed that 12% more of the shortsleepers had died when they were followed up, compared to themedium sleepers。

　　他的分析表明，睡眠较少的人中有超过12%的人比中等睡眠时间的人早死。

　　However, 30% more of the long sleepers had died,compared to the medium sleepers。

　　但是，与中等睡眠时间的人相比，睡眠较长的人死亡率竟高出30%。

　　But can it really be true that getting nine hours’sleep is worse for you than getting five?

　　但是睡9个小时真的比睡5个小时更具伤害性吗？

　　There are different ways of looking at this。

　　其实可以从不同的角度来看此问题。

　　Cappuccio was aware of the possibility that peoplesleeping too long might be depressed, or might be using sleepingpills. He corrected for this, though, and found the association wasstill there。

　　卡普里奥明白调查中睡眠太久的人或许心情过于压抑又或者服用了安眠药。虽然他纠正了这一点，但是他发现睡眠太久与死亡率之间仍存有关联。

　　His own theory is that people who sleep for more thaneight hours sometimes have an underlying health problem that is notyet showing in other symptoms。

　　他的观点是那些睡眠超过8个小时的人会存在一些健康隐患，只不过当下并未显现出其他症状。

　　So, it’s not the long sleep that is causing theincreased mortality risk, it’s the hidden illness。

　　所以，并不是睡眠过久导致了死亡率上升，那些隐疾才是罪魁祸首。

　　But can we say that eight hours are better thansix?

　　但是睡8小时一定比6小时好吗？

　　The magic number, according to Dr Gregg Jacobs, ofthe Sleep Disorders Center at the University of MassachusettsMedical School may actually be seven。

　　根据麻省大学医学院睡眠障碍中心的格雷格·雅各布斯博士所说，睡眠最合宜的时间应该是7小时。

　　He points, for example, to the National SleepFoundation’s annual pollof a random sample of adults in the US

　　比如，他指出，美国国家睡眠基金会的年度投票是在美国成年人当中随机抽取的样本。

　　"The typical adult today [in that poll] reports sevenhours of sleep. And that actually seems to be the median sleepduration in the adult population around the world. That suggeststhere’s something around seven hours of sleep that’s kind ofnatural for the brain."

　　“投票显示，现在大部分成年人都睡7个小时。而这应该也是全世界成年人的中等睡眠量。这说明7小时睡眠或许对大脑来说比较自然。”

　　But if you enjoy sleeping, spend a lot of time in bedand feel good, you’re probably just fine. There’s no hard evidencethat extra time asleep, or just lying down and relaxing, is goingto kill you。

　　但是如果你非常享受自己的睡眠，在床上时间虽多但仍感觉良好，那应该并无大碍。现在并没有确凿的证据证明睡眠过多或躺在床上放松自己就是自杀。

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