New University of Minnesota research suggests there are real health benefits to getting seven to eight hours of regular nighttime sleep.
Researchers studied 3,000 men over age 67. Researcher Misty Paudel says they found higher mortality rates among men whose sleep patterns were irregular and whose activity levels were uneven.
"If they had restlessness nights and never really settled down to low activity period or if they weren't that active during the day, those rhythms were not as robust. And that was associated with higher rates of mortality," Paudel said.
Paudel said the study suggests that waking early, staying up late, and having severely disturbed sleep patterns, may have a detrimental impact on older men's health.