Sure, we've heard that sleeping with your makeup on or sleeping with your face smushed into your pillow can cause you to age. But a new study says, it's not how you sleep, but how long you sleep that determines aging.
Researchers at Singapore's Duke-NUS School of Medicine say sleep quantity, not quality, can prove to be a factor for older adults. The study involved 66 Chinese adults aged 55 and over, taking MRI scans and administering cognitive assessments at two-year intervals. After looking at the participants' brain volumes, cognitive performance, and their self-reported sleep patterns, researchers discovered lower sleep duration can quicken brain aging.
Just one hour of sleep reduction increased the rate of brain ventricle enlargement, which is a known marker for age-related cognitive decline and neurodegenerative diseases. Meanwhile, sleep quality wasn't shown to have any significant affect on brain aging or functioning.
"Our findings relate short sleep to a marker of brain aging," lead author June Lo said in a release.
Numerous recent studies on sleep duration and quality have tried to pinpoint the ideal hours of sleep for older adults. A University of Oregon study said six to nine hours is the ideal range to ensure optimal cognitive performance. Meanwhile, a British study said it's actually six to eight hours that are optimal.
Authors of the Duke study seem to suggest that somewhere in between could be the "sweet spot," adding that future research will look at the long-term effects of sleep duration and quality.
That's enough to make us get to bed early.