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(lái)父母?jìng)円恢币詠?lái)都是對(duì)的。一項(xiàng)最新研究報(bào)告稱，早睡不僅是得到充足睡眠的關(guān)鍵，而且有助于改善青少年的情緒。

    這項(xiàng)由哥倫比亞大學(xué)醫(yī)學(xué)中心開(kāi)展的研究表明，青少年缺乏睡眠可能會(huì)引發(fā)抑郁以及自殺的念頭。

    研究報(bào)告的主要撰寫(xiě)人詹姆斯？岡維西說(shuō)："有理論認(rèn)為睡眠不足是導(dǎo)致抑郁的風(fēng)險(xiǎn)因素之一，它與其他風(fēng)險(xiǎn)和保護(hù)因素相互作用，通過(guò)多種可能的因果途徑，造成這種情緒失調(diào)。我們的研究結(jié)果與這一理論是一致的。"

    "所以，充足、高質(zhì)量的睡眠可以成為防治抑郁癥的一項(xiàng)措施。"研究報(bào)告在上周五的《睡眠》雜志上發(fā)表。

    該研究對(duì)15659名大學(xué)生和中學(xué)生的夜間作息習(xí)慣進(jìn)行了追蹤調(diào)查，發(fā)現(xiàn)那些經(jīng)常在午夜后就寢的學(xué)生患抑郁癥的風(fēng)險(xiǎn)比那些在晚上10點(diǎn)前就上床睡覺(jué)的學(xué)生高24%.

    研究稱，晚睡者產(chǎn)生自殺念頭的風(fēng)險(xiǎn)也要高20%.

    美國(guó)睡眠藥物學(xué)會(huì)建議，青少年每晚睡眠時(shí)間至少要達(dá)到9個(gè)小時(shí)。晚上10點(diǎn)前就寢的人稱他們平均每天的睡眠時(shí)間約為8小時(shí)10分鐘。

    但那些在午夜后睡覺(jué)的人的睡眠時(shí)間明顯少很多。

    研究報(bào)告說(shuō)，每晚睡眠時(shí)間為五小時(shí)或更少的青少年患抑郁癥的幾率高71%,出現(xiàn)自殺傾向的幾率高48%.

    岡維西說(shuō)："目前存在這樣一種普遍看法和社會(huì)預(yù)期，認(rèn)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(shí)上青少年可能需要更多睡眠。"

    "研究發(fā)現(xiàn)，青少年上學(xué)的時(shí)間提早了，但卻沒(méi)有提早就寢來(lái)對(duì)此加以補(bǔ)償，而且上學(xué)時(shí)間提早與嚴(yán)重的睡眠剝奪有關(guān)。"