"In a study of more than 1,500 10- to 19-year-olds, researchers found that sleep, when measured in one way, was related to body weight. Measured a different way, however, it was not."

"The findings, which are published in the journal of Pediatrics, do not mean that previous studies linking sleep loss to excess pounds are wrong. But they do suggest that the measurements researchers use to gauge sleep deserve closer scrutiny, the study authors say. "

"Specifically, their study found that there was a relationship between adolescents' weight and their self-reported sleep habits -- gauged by the question, "How many hours of sleep do you usually get a night?""

"Children and teens who said they typically slept for more than 9 hours were less likely to be overweight than their peers who slept for 7 to 9 hours."

"But when the study participants were asked to keep detailed diaries on their activities over two 24-hour periods, there turned out to be no link between sleep and weight."

""Our study shows that there is more work to be done in understanding the association between sleep and weight," said study co-author Dr. Kristen L. Knutson of the University of Chicago. "

"It does not, however, discount past research showing that sleep deprivation may spur weight gain, Knutson told Reuters Health. "

"A number of studies have found that adults and children who get relatively little sleep each night are more likely to be overweight than their peers who catch more Z's. More importantly, Knutson pointed out, controlled sleep-lab studies, where sleep was measured objectively, have suggested that sleep loss can alter hormones involved in appetite and metabolism."

"In one small study, healthy young men who
... read the whole article