It seems parents have long been right. Going to bed early is key to getting enough sleep and helping adolescents feel on top of the world, a new study reported.

    A lack of sleep among youngsters may trigger depression and suicidal thoughts, according to the study by the Columbia University Medical Center.

    "Our results are consistent with the theory that inadequate sleep is a risk factor for depression, working with other risk and protective factors through multiple possible causal pathways to the development of this mood disorder," said lead author James Gangwisch.

    "Adequate quality sleep could therefore be a preventative measure against depression and a treatment for depression," he added in the study published in the Friday issue of Sleep magazine.

    The study followed the nightly habits of some 15,659 college and high-school students, and found those who consistently went to bed after midnight had a 24 percent higher risk of depression than those who turned in before 10:00 pm.

    Night owls also ran a 20 percent higher risk of battling suicidal thoughts, the study added.

    The American Academy of Sleep Medicine recommends that adolescents should sleep at least nine hours or more a night. Those who were tucked in before 10:00 pm reported they slept on average about eight hours and 10 minutes.

    But that amount of sleep dropped significantly for those in bed after midnight.

    And adolescents who slept five hours or less a night were 71 percent more likely to suffer depression and 48 percent more at risk of becoming suicidal, the study said.

    "It is a common perception and societal expectation that adolescents do not need as much sleep as pre-adolescents, yet studies suggest that adolescents may actually require more sleep," said Gangwisch.

    "Studies have found that adolescents do not go to bed early enough to compensate for earlier school start times, and transitions to earlier school start times have been shown to be associated with significant sleep deprivation."

    看來父母們一直以來都是對的。一項最新研究報告稱，早睡不僅是得到充足睡眠的關鍵，而且有助于改善青少年的情緒。

    這項由哥倫比亞大學醫學中心開展的研究表明，青少年缺乏睡眠可能會引發抑郁以及自殺的念頭。

    研究報告的主要撰寫人詹姆斯？岡維西說："有理論認為睡眠不足是導致抑郁的風險因素之一，它與其他風險和保護因素相互作用，通過多種可能的因果途徑，造成這種情緒失調。我們的研究結果與這一理論是一致的。"

    "所以，充足、高質量的睡眠可以成為防治抑郁癥的一項措施。"研究報告在上周五的《睡眠》雜志上發表。

    該研究對15659名大學生和中學生的夜間作息習慣進行了追蹤調查，發現那些經常在午夜后就寢的學生患抑郁癥的風險比那些在晚上10點前就上床睡覺的學生高24%.

    研究稱，晚睡者產生自殺念頭的風險也要高20%.

    美國睡眠藥物學會建議，青少年每晚睡眠時間至少要達到9個小時。晚上10點前就寢的人稱他們平均每天的睡眠時間約為8小時10分鐘。

    但那些在午夜后睡覺的人的睡眠時間明顯少很多。

    研究報告說，每晚睡眠時間為五小時或更少的青少年患抑郁癥的幾率高71%,出現自殺傾向的幾率高48%.

    岡維西說："目前存在這樣一種普遍看法和社會預期，認為青少年不像兒童那樣需要那么多睡眠，然而研究表明，事實上青少年可能需要更多睡眠。"

    "研究發現，青少年上學的時間提早了，但卻沒有提早就寢來對此加以補償，而且上學時間提早與嚴重的睡眠剝奪有關。"