A study published Monday found that people who sleep less tend to be fat, and experts said it's time find if more sleep will fight obesity.

"We've put so much emphasis on diet and exercise that we've failed to recognize the value of good sleep," said Fred Turek, a physician at Northwestern University.

Monday's study from Eastern Virginia Medical School in Norfolk covered 1,000 people and found that total sleep time decreased as body mass index--a measure of weight based on height--increased.

Men slept an average of 27 minutes less than women and overweight and obese patients slept less than patients with normal weights, it said. In general the fatter subjects slept about 1.8 hours a week less than those with normal weights.

"Americans experience insufficient sleep and corpulent bodies. Clinicians are aware of the burden of obesity on patients," the study said.

"Our findings suggest that major extensions of sleep time may not be necessary, as an extra 20 minutes of sleep per night seems to be associated with a lower body mass index," it added.

"We caution that this study does not establish a cause-and-effect relationship between restricted sleep and obesity (but) investigations demonstrating success in weight loss via extensions of sleep would help greatly to establish such a relationship."

The study was published in the Archives of Internal Medicine along with an editorial by Turek and Northwestern colleague Joseph Bass commenting on it and related research.

In an interview with Reuters, Turek said some studies have shown sleep deprivation causes declines in an appetite suppressing protein hormone called leptin, and increases in another hormone that causes a craving for food. In addition neuropeptides in the brain governing sleep and obesity appear to overlap, he said.

Obesity has been rising dramatically in developed countries and reached epidemic levels in the United States, it added, leading to a variety of health problems.

本周一發布的一項研究表明睡眠不足的人易發胖。專家們表示現在是時候調查一下睡得多是否有助于減肥。

美國西北大學的醫學教授弗萊德·塔瑞克說：“我們一直過份強調節食和鍛煉，以至于忽略了良好睡眠的作用。”

周一，位于美國弗吉尼亞州諾�？耸械臇|維吉尼亞醫學院發布了這份研究。對1000名受試者的研究顯示累計睡眠時間和體重指數剛好成反比，體重指數是一種以身高為基準來衡量體重的方法。

該研究顯示男性的睡眠時間平均比女性少27分鐘，而肥胖病人比正常體重的病人睡眠時間少。總的來說，體態肥胖的受試者每周比正常體重的受試者少睡約1.8小時。

該研究指出：“美國人普遍睡眠不足﹑體型超標。醫生們已經認識到肥胖給病人帶來的負擔。”

同時該研究還顯示：“我們的調查結果表明沒有必要大量增加睡眠時間，每晚多睡20分鐘似乎有助于降低體重指數。”

“我們要提醒（大家）的是這項研究的結果并不足以證明節制睡眠和肥胖之間的因果關系，（然而）調查顯示延長睡眠時間確實可以成功減輕體重，這對于證明這一因果關系非常有幫助。”

該研究結果發表在美國《內科學文獻》期刊上，塔瑞克和西北大學的同行約瑟夫·貝斯共同對上述研究結果及其相關研究發表了評論。

在接受路透社采訪時，塔瑞克說已經有研究表明睡眠不足會導致“瘦體素”分泌減少，而另一種增強食欲的荷爾蒙分泌增多，“瘦體素”是一種抑制食欲的蛋白質荷爾蒙。此外，他還說大腦中調節睡眠和肥胖的神經肽似乎重合在一起。

該研究還提到，近年來發達國家肥胖癥的發病率以驚人速度增長，在美國肥胖已成為一種流行病，并且引發多種健康問題。