Wondering how to lose weight without much effort? Don't stress and get some good sleep. A new Kaiser Permanente study has found that people with the lowest stress levels and who also got more than six hours, but not more than eight hours, of sleep were most likely to lose at least 10 pounds. Nearly 500 participants from Kaiser Permanente in Oregon and Washington took part in the study, which measured whether sleep, stress, depression, television viewing, and computer screen time were correlated with weight loss. Several previous studies have found an association between these factors and obesity, but few have looked at whether these factors predict weight loss. "This study suggests that when people are trying to lose weight, they should try to get the right amount of sleep and reduce their stress," said lead author Charles Elder. "Some people may just need to cut back on their schedules and get to bed earlier. Others may find that exercise can reduce stress and help them sleep. For some people, mind/body techniques such as meditation also might be helpful," he added. The researchers, however, cautioned that their findings might not apply to all groups trying to lose weight. The study has been published in the International Journal of Obesity.