BOSTON, July 25 (UPI) -- Older people don't need as much sleep as younger people, researchers at Boston's Brigham and Women's Hospital & Harvard Medical School said.
The study, published in the Current Biology, found that when asked to stay in bed for 16 hours in the dark each day for several days, younger people get an average of nine hours of sleep compared to 7.5 hours for older people.
"The most parsimonious explanation for our results is that older people need less sleep," Elizabeth Klerman of Brigham and Women's Hospital & Harvard Medical School, said in a statement. "It's also possible that they sleep less even when given the opportunity for more sleep because of age-related changes in the ability to fall asleep and remain asleep.
The findings apply only to healthy individuals taking no medication and having no medical conditions or sleep disorders, Klerman said.
However, the study also found that most healthy people, and young people in particular, don't get as much sleep as they need.
Klerman and colleague Derk-Jan Dijk, of the University of Surrey in England compared the capacity for sleep in young people ages 18 and 32 to older people age 60 to 72.
