Early to bed and early to rise makes a man healthy, happy and slim, according to new research.

新研究显示，早睡早起有助于身体健康，保持心情愉悦，还有瘦身功效。

A study that analysed the DNA¹ of self-professed 'nights owls³' and 'morning larks⁵' found that people who like to rise early tend to be thinner than those who go to bed later.

通过分析“夜猫子”和“早起鸟”的DNA，研究发现：早起的人会比晚睡的人更瘦。

They are also less prone⁶ to depression and less likely to suffer from insomnia⁷.

早起的人罹患抑郁症和失眠症的几率也更小。

Almost 90,000 people were asked if they were naturally a morning or a night person and had their DNA analysed.

此项研究让近9万人选择自己是“夜猫子”还是“早起鸟”，并分析了他们的DNA。

This revealed 15 genes⁸ that were linked to a person being a 'lark⁴' or an 'owl²'.

研究结果表明，人类体内有15个基因与“早起还是晚睡”有关。

A preference for mornings rose with age, with more than twice as many of over-60s describing themselves as morning types than under-30s.

年龄越大，人起的就越早。认为自己是早起类型的人中，60岁以上的比30岁以下多出一倍。

Women were more likely to enjoy mornings than men, the journal Nature Communications reports.

《自然通讯》期刊中有文章表明，女性比男性更爱早起。

The researchers, from the California-based genetic⁹ testing company 23andMe aren't sure why a person's body clock might be so strongly linked to health.

此项研究的研究人员来自总部位于加利福尼亚州的个人基因检测公司23andMe，他们也无法确知生物钟与健康之间为何如此密切相关。

But it might to be as simple as too many late nights taking their toll¹⁰ on evening types.

但这背后的原因也许很简单，经常熬夜让那些夜猫子的身体付出了代价。

For instance, the study suggested that a gene that is involved in body weight also affects whether someone is at their best in the morning or at night.

举例来说，该研究表明，与体重有关的一个基因会影响人们的最佳状态是在早上还是夜晚。

Researcher David Hinds¹¹ said: 'We like to think of our preferences and behaviour as core to who we are and it's interesting to see how our biology influences these things, like whether you are a morning person or a night owl.

研究人员大卫·海因兹说：“我们喜欢把我们的偏好和行为当作‘我们是谁’这个问题的核心。研究生理特质如何影响人早起或晚睡等行为偏好其实挺有趣的。”

'With large genetic databases available for study, we can uncover the genetics behind a variety of conditions and diseases and hopefully reach a better understanding of how we differ from one another.'

大卫还说：“现如今，可供研究的基因库数据庞大，我们可以发现各种病症背后的遗传学原理，有望对个体特殊性有更深的理解。”

But night owls needn't despair because a previous study found them to be brainier than those who leap out of bed when it is still dark.

但“夜猫子”们也不必沮丧。之前的一项研究表明，晚睡的人比那些天还没亮就起床的人更聪明。

To be precise, the brainiest go to bed at 29 minutes past midnight - while least clever turn off the bedroom light at 11.41pm, the British study found.

确切地说，根据一项英国研究，最聪明的人在零点29分时睡觉，而智商最低的那些人在晚上11点41分关灯上床。

It is thought the division into larks and owls has its roots deep in evolution, with early risers in the Stone Age taking the initiative in food gathering¹², while late bidders¹³ stood guard late into the night.

人们认为，“夜猫子”和“早起鸟”这种分类可以从人类进化上找到深层原因。在石器时代，早起的人带头采集食物，晚睡的人则在夜晚守夜。